Shimon was born in 1921 near Minsk, Belarus, to Malka and Yosef. His father had to flee and made aliyah in 1925, while Shimon, his mother and his sister arrived in February of 1927, on the last ship to leave Odessa. After two weeks, he arrived in Jaffa, and his father met them and took them to Jerusalem.
From 1936 to 1939, Shimon studied in the Mikve Israel Agricultural School. He then enlisted in the Hagana.
In 1942, he joined the Palmach’s Jerusalem Company; in 1945, he was sent to the squad commanders’ course. He was active in Aliyah Bet, helping Jews enter the country through Syria and Lebanon, during a long period, a task which he saw as his personal mission. In fact, when he was sent back to his regular work, he refused and went home. A few months later, a Lehi member approached him to recruit him for the underground. Shimon agreed, but he said that he would return to the Hagana if they approached him.
In the Lehi branch in Jerusalem, he was active against the British, including in an operation which involved bombing a locomotive pulling a freight train to Jerusalem in June 1946. He surveyed the tracks all the way from Beit Safafa to the Har Tov station, under cover of being a nature guide. His family home on Alfandari Street in Mekor Baruch was a place to offer first aid to underground members, and his mother assisted. His father worked in Hadassah Hospital, and he was a Lehi supporter as well, who used his position to help the underground.
In August 1947, Simon was summoned by the Hagana to go to the platoon commanders’ course. He told his Lehi commanders, and thus concluded his service with the underground. However, in February 1948, they called him and asked him to join Mordechai “Dror” Ben Uzziah to blow up Tanus House. He surveyed the location and helped plan the operation. During the operation, he gave cover to Lehi members with his Hish unit, and he also helped transport the wounded. Throughout the War of Independence, he was the commander of the special operations unit in the IDF.
In August 1950, he married Zipporah Matusk, and they had a son and grandchildren. Shimon worked in the Antiquities Authority as an administrator and security coordinator throughout the country for thirty-four years, until he retired.
Shimon finally returned to his original profession, gardening.