A 46-year-old man was taken conscious to Khoo Teck Puat Hospital after he was hit by a minibus on Monday morning.
The police were alerted to the accident in Mandai Road at 8.52am.
The male driver was arrested for driving a vehicle without the owner's consent. He also does not possess a valid driving licence, the police said.
A photo sent by an eyewitness to Chinese-language broadsheet Shin Min Daily News showed the victim, who appeared to be a foreign worker, wearing a company uniform.
He crossed the road several times shortly before the accident, the paper reported.
Shin Min said the minibus driver knew the owner of the vehicle but did not have the owner's permission to drive the bus that day.
Eyewitness Qiu Guoxing told Shin Min that six medical personnel from a nearby army camp attended to the victim at the scene.