The so-called Syrian Observatory for Human Rights, which posted the video, says the beheading was conducted by militants from the Islamic State of Iraq and the Levant (ISIL).
The identity of the victim could not be verified in the video.
A three-minute part of the video shows the crowd laughing and taking photographs as the militants cut off victim’s head. Several children are also among the crowd.
Since the beginning of the crisis in Syria in March 2011, many similar videos have emerged, depicting horrendous crimes, including decapitation and cannibalism, committed by the foreign-backed militants against the people in Syria.
A video footage posted online on January 26, showed several mutilated bodies in the western suburb of Aleppo that reportedly belong to the civilians who were executed by ISIL militants.
Another video posted online on May 12, 2013, showed Takfiri militant, Khalid al Hamad, known by his nom de guerre, Abu Sakkar, eating an organ of a dead Syrian soldier.
In an interview with the state-run BBC in July 2013, Abu Sakkar threatened to commit more gruesome murders if foreign-backed terrorists in Syria do not receive more military aid from abroad.
Reports show that the Western powers and their regional allies - especially Qatar, Saudi Arabia, and Turkey - are supporting the militants operating inside Syria.
SHI/SHI