After initial successes, the ASP was banned by Syria's de facto leader, Adib ash-Shishakli, in 1952, as he considered it to be too powerful a political rival.

After Hafez al-Assad took power in 1970, the ASU entered into negotiations about a coalition government, and agreed to join the National Progressive Front (NPF) in 1972.

One minor faction under Fawzi Kiyali accepted the constitution, and retained both the ASU name and the NPF membership, while most members followed party leader Jamal al-Atassi into opposition, by renaming themselves the Democratic Arab Socialist Union (DASU).

Both the ASU and DASU distanced themselves from Anwar Sadat's government, particularly after his policies towards Israel became more conciliatory, and their close relations with Cairo were lost before the Egyptian mother party itself dissolved in the mid-1970s.

The Arab Socialist Union Party of Syria (i.e., the ex-Kiyali faction), which glorifies the Baath presidency and shows virtually no independence from the government, has long been led by Safwan al-Qudsi.

It remains an illegal party and has been subject to sporadic repression; although it became semi-openly active after the accession of Bashar al-Assad to power in 2000, and under the limited liberalization that followed.