"Angry people are preventing commuter buses from carrying passengers. People are just stranded," Nhamo Tembo told AFP. He was trying to travel from Epworth, a poor suburb, east of the capital Harare.
"We want [President Emmerson] Mnangagwa to know our displeasure in his failure," protester Mthandazo Moyo told AFP.
On Saturday, President Mnangagwa announced that the price of petrol would more than double.
It is intended to improve supplies as the country struggles with its worst fuel shortages in a decade.
Petrol prices rose from $1.24 a litre (£1.11) to $3.31 starting Sunday.