The activists met Sunday afternoon on Old Spanish Trail, the same area where a woman was attacked after getting off a METRO bus last month.
They passed out fliers with a sketch of the attacker and called on local agencies to address the problem.
Organizers said they are calling on city, county and METRO leadership to combine their resources "to see what measures need to be taken in order for us to fight this scourge in the city of Houston."
The activists say they're also upset about thousands of untested rape kits at the Houston Police Department. They want the city to make it a priority to test those kits.