The police said they had registered a case against her colleague on the basis of a complaint by her father.
Amanpreet Kaur was posted at the Nidhan police station in the Ludhiana Rural police district.
Her body was found hanging to a ceiling fan in one of the rooms in the police station last night, the police said.
The victim's father, in a complaint alleged that one of her colleagues, identified as Nirbhay Singh, used to harass her.
Senior policeman Surjit Singh said that "a case has been registered against Nirbhay Singh, who was posted as the police station 'munshi', under section 306 (abetment of suicide) of the IPC on the complaint of her father".
The body has been sent for post-mortem, the Senior policeman added.