In a report on its website, Dawn says Murtaza Rizvi was murdered early Thursday. His body was found in an apartment in an upscale area of the city.
It was not clear if the killing was related to his work.
Rizvi was the editor of magazines at the Dawn newspaper group and a respected journalist.
Police officer Farukh Ali said Rizvi was strangled.
The paper said Rizvi's hands were tied and his body had signs of torture.
Pakistan is one of the world's most dangerous countries for journalists. Threats against reporters come from Islamist militants, political parties, criminal gangs and security forces.