Sayel was born on 30 September 1932 in the village of Kafr Qalil village in the Nablus District. He, joined Awarta Elementary school and in 1950 completed his secondary education at Al Salahiyeh School.

Sayel lived the period of the great Palestinian revolution and was aware of the British intentions to control Palestine with the aim of establishing the Zionist entity on its soil.  He also experienced the dramatic events of the which motivated him to start the work for the liberation of Palestine.  To that end, he strived to accomplish the education and invest in all the available capabilities along with having the belief in the culture and practice of the revolution by being attentive to any national or pan national activity.

  In 1951, Saad Sayel joined the Jordanian army and was accepted to the Jordanian Military Academy to specialise in military engineering. Afterwards, he enrolled for several military training courses which formed the stage of his educational, vocational and training achievement as well as the stage of acquiring the necessary military sciences and skills in several countries:
- 1954 -A military engineering course at the Royal Military Academy Sandhurst. 
- 1956 - An air defence course in Egypt.
- 1958 - A course in Iraq about classifying and designing bridges.
- 1959 An advanced course in military engineering at the Royal Military Academy Sandhurst in England. 
-1960 An advanced course in military engineering at West Point Academy in the United States of America.
-1966 A course at the Command and General Staff College at West Point military Academy in the United States of America.  
- Additionally, Saad Sayel joined a number of military courses in the Soviet Union, Pakistan and other countries which enabled him to excel in this field and to get a sequence of promotions and military ranks in the Jordanian Arab Army until he became a Staff Colonel and the commander of Al Hussain Bin Ali infantry Brigade which was based in Kafarnjah and the Jordan Valley. Sayel’s choice to lead a military life reflects his overwhelming commitment and his immense urge to contribute effectively to the Palestinian national cause namely when the revolution kicked off in 1965. 
-Saad Sayel was determined to weave strong ties with the early founders of the revolution and specifically with FATH Movement. Undoubtedly, he played an effective and coordinative role between the Palestinian Revolution leadership and the Jordanian  Army during Al Karama Battle which occurred on 21 March 1968. Following the 1970 September events, he  and most of his subordinates in the unit which was  under his command  joined the Palestinian revolution in order to  confront the plots which aim at  ending it.  
-After the exit of the Palestinian resistance from Jordan in 1970-1971, Abu al Waleed started  reorganising and forming the Jordanian  officers and soldiers who decided to join  the resistance units  to build the Yarmouk combat Brigade which played a distinctive role in strengthening the presence of the Palestinian revolution in Lebanon  and in defending the refugee camps against the surrounding dangers. In addition, he masters minded the process of reorganizing and restructuring the resistance forces in Lebanon by introducing the units and ranking system.  Later on, he was elected as a member in the Palestinian National Council (PNC).
- In 1980 Abu Al Waleed was elected to be a member at Fateh Central Committee and was promoted to a Brigadier General and afterwards to a Major General for the Central operations Authority as well as being a member in the general command of Al Asifah Forces (The storm) and a member in the apparatus which commanded the Occupied Territories.

Major General Abu Al- Waleed worked closely with both Abu Amar and Abu Jihad while demonstrating the ability to combine the two roles as a military and as a political leader. He was a genuine field person who would believe only in what his eyes can see and what his hands would touch. He has never dealt with buzz slogans yet used to base  his decisions on research and  study. He was well aware of the balance of power and would rely only on reliable sources of information. Despite being very critical of  radical and the wrong policies of some leaders, he was able to  maintain the channels of communication with all the forces wisely and patiently while focusing on the main objective and ignoring the secondary matters with the aim of strengthening the internal front. 

For this specific reason, he was highly respected by the entire Lebanese and   the Palestinian forces.
In July 1981, General Sayel,  led with high efficiency and with distinctive skill what is known as the  Battle of  Artillery in response to the Israeli air attacks on the refugee camps and the Palestinian military sites in Lebanon  during which the Palestinian artillery shelled Nahariya and  several Israeli military positions for the  first time . 

At the turn of 1982, Abu Al Waleed started to realise that the big confrontation with the Israeli occupation is inevitable. Based on that, he  drafted a comprehensive defence plan and followed it up to make sure of its applicability on the ground after  getting the approval of the General Commander, Yasser Arafat and the Palestinian Military Council. 

Therefore, in order to understand fully the phenomenal Palestinian – Lebanese steadfastness during the 1982 war on Lebanon, we must refer to the central role of Abu Al- Waleed which qualified him for the title : “The Field Marshal of Beirut” . 

In the meantime, he was in charge of the negotiations with the Special American envoy, Philip Habeeb, at the premises of the then Lebanese Prime Minister Shafiq Al Wazzan through which he assured a dignified exit for the Palestinian forces from Lebanon and the security of the refugee camps let alone the political gains which resulted from the legendry Palestinian resistance over a period of three months which was described by military analysts as a historical event.  

Truly, Abu Al- Waleed was the master mind and the designer of the event. 

After agreeing on the exit mechanisms of the PLO leadership from Lebanon, Abu Al Waleed rejected the idea for a secret departure of Arafat and the leadership fearing attempts on their lives. He preferred an official and ceremonial exit because this would bear many implications and symbols. 
During those crucial moments Abu Al -Waleed used to say “There should not be any worry about the PLO after Beirut because it will exist and persist as long as the Palestinian people exist but what is  important is rearrange  the Palestinian military  capacity in order to  keep it as  a main factor in the conflict equation .

Abu Al Waleed led a number of military operations and captured eight Israeli soldiers who were exchanged later on with the Lebanese and Palestinian prisoners in the Ansar detention camp. 
The Palestinian leadership formed a committee under Abu Al- Waleed to oversee an orderly exit from Beirut which would allow the fighters to leave with their personal weapons, belongings and equipment. Lists of names for each ship were prepared and the fighters were asked to gather at the Municipal play ground in Beirut. Abu Al- Waleed made sure to be on site in order to observe closely the logistics of the departure. After Arafat’s arrival to Greece, Abu Al Waleed arranged on 1 September 1982 for an official visit to the martyrs’ cemetery in Beirut (Qasqass Neighbourhood), per his desire, all participants went on foot despite the dangers.

He was the last to board the ship to Tartous harbour in Syria. While on the Board of the Greek  boat on his way to Syria with the last group of the cadres and fighters, Abu Al Waleed arranged for a meeting with members of Military Council in the Beqaa Velley and addressed them:” We have to convene  within  72  hours because the time  factor is very crucial. Our fate is to complete the path and fulfil the oath to which we committed ourselves. There are big  tasks ahead of us , most importantly , we have to reorganise  and  rebuild  our forces which already  exist in the Beqaa Valley and North Lebanon and  help the Lebanese National resistance   with the aim of perpetuating the battle with the enemy and sap its  energy. Our human and military capabilities are adequate and we should optimise these resources in order to prove that the strategic objective of the Israeli assault is a failure”.

Abu Jihad, Abu Iyad and Abu Al Waleed headed to Syria in order to regroup the forces which left Lebanon but 3 days later Abu Al Waleed decided to return to Lebanon in order to translate his ideas into a reality. 

He instantly started the Process of organising and forming the forces in the Beqaa Valley in an adequately and efficiently. This plan was necessary to start the military activities and use all the available resources and take by surprise the Israeli forces which were deployed in the Western Sector of the Beqaa Valley.  

 
On Monday the 27th of September 1982 which coincided with the first day of Al Adha Feast, the Israeli hands of treachery and betrayal got Major General Abu Al Waleed  when his  patrol was  caught in an ambush on the road that  links Al Reyak with Byblos while he was on a field tour to inspect the resistance fighters  In the Beqaa Valley . A driver was martyred and Abu Al Waleed sustained serious wounds in the thigh to which he succumbed at 23:00 of the same day. He was Buried at the Martyrs’ cemetery in Al Yarmouk refugee camp near Damascus.

Thus, with the ascension of Abu Al Waleed, Palestine has lost one of its most distinguished symbols  who can be regarded as an indispensable military and political asset. The late leader Yasser Arafat described him :” Abu Al Waleed was  one of the solid Palestinian national pillars  for he was   a perfect military  person, loyal  to his duties, capable of running the  affairs  of our forces which are deployed in the entire Arab World. He was a model for giving , perseverance and candid opinion”.  

During the Arab Summit in Fez, King Hussain  addressed Yasser Arafat saying:” Your steadfastness and outstanding performance in Beirut  is associated with a General who the Jordanian Army is proud that he was one of its commanders, ..  He was the proficient and diligent general Saad Sayel”

May god bless the soul of the great commander, Saad Sayel – Abu  Al Waleed and give him eternal peace.