According to activists Ali Farzat, whose work is strongly critical of the government, was forced out of his car in Damascus, badly beaten and dumped at the side of the road, BBC writes.
“In one of his latest cartoons, Ali Farzat shows President Assad sweatily clutching a suitcase while he tries to hitch a lift with the Libyan leader, Col Gaddafi, who is furiously driving a getaway car.
The Syrian cartoonist has produced a stream of images like this in the past few months that have directly attacked the Syrian leader.
In one, President Assad is shown patiently white-washing the shadow of a huge security thug on a wall, while the real man stands untouched. The caption reads: "Lifting the emergency law".
Another shows Mr Assad flexing in uniform in front of a mirror that reflects back a dominant, muscular image, overshadowing his puny figure.
For 40 years, Ali Farzat has been skewering the mismatch between rhetoric and reality in the Arab world.
In his meticulous drawings, mostly without captions, he has shown the overbearing brutality of bureaucracy, the hypocrisy of leaders, and myriad other injustices of daily life that have resonated across the Middle East.
When President Assad first took power, Ali Farzat was allowed to start an officially-sanctioned satirical magazine as part of what was intended to be a new era of openness. But it was soon closed down.
What has changed in his work as the Syrian uprising has grown is his readiness to target real people - President Assad above all - rather than archetypes of unfettered power.
His beating-up by security forces shows that he has hit home and that the authorities' tolerance for dissent is touching zero."
Ali Farzat is now recovering in hospital.