A teenage boy was killed and a two-year-old boy critically injured when a taxi crashed into them in Meadowlands on Sunday night, Johannesburg emergency services said.

Spokesperson Percy Morokane said the two boys had been crossing a busy road when a taxi hit them shortly before 9pm.

"The 14-year-old boy died on the scene and the toddler was rushed to the Chris Hani Baragwanath hospital in a critical condition," Morokane said.

While advising motorists to be on the lookout for pedestrians while driving around busy areas, he warned people to wear reflective clothing when walking at night.

"Parents should also keep their children under a very watchful eye... know where your children are especially at night. Most importantly, everyone should wear reflective gear at night and use pedestrian crossings when crossing busy roads like Van Onselen street," he said.

Captain Nomvula Mbense could not immediately comment on the whereabouts of the taxi driver.