The Taxi Workers Alliance of Pennsylvania held a vigil on Market Street to pay tribute to Hafiz Sarafqaz.
He was shot and killed by a passenger in a robbery attempt Wednesday night.
The group also wanted to bring attention to what they call dangerous and unsafe working conditions for cabbies in the city.
"Cab drivers are 60 times more likely to get killed on the job, and yet there are no benefits to families when this happens," said one demonstrator.
The alliance also pointed out that hazards on the job get passed on to passengers.