Only a few buses with the state-owned Dakar Dem Dikk Corporation were operating, and taxis and buses which usually ply routes between the suburbs and the city centre were not running, AFP reporters saw.
Many children and workers walked to school or their workplaces.
Unions have set down 10 demands that include an end to "harassment by the police, customs, gendarmerie and... the arrest of drivers," said Gora Khouma, a union official.
They are also demanding a crackdown on clandestine drivers who compete illegally with authorised businesses.
"We didn't launch this strike to bother the public but to find a solution to our problems," Khouma said.
"For years, we've been signing agreements with the government which have not been upheld."