Kartik Chattopadhyay (50) was found hanging from the ceiling of his room in his residence at Vidyasagar Pally, they said.
The police have found an alleged suicide note from the room, which stated work pressure as the reason behind him taking the extreme step, they said.
Chattopadhyay was a sub-inspector at Park Street police station in Kolkata.
His two daughters and wife were away when the incident occurred, they said.