The officer, known as Marilyne, had not seen her boyfriend, also a police officer, for two months, reported newspaper Aujourd'hui.
The man, only named as Ludovic, had just returned from a two-month trip to the West Indies.
The newspaper reported that the couple were together on Saturday evening in Bagneux, a southern suburb of Paris.
After an evening of discussions about their relationship, 28-year-old Marilyne became upset and used her police weapon to shoot her boyfriend. She then turned it on herself.
At a certain point in the evening, Marilyne had called her mother to share her unhappiness. Whether this was before or after she had shot her 26-year-old boyfriend is not known.
Her distress was such that her mother asked her brother to go to the apartment to see his sister. He went in the early hours of Sunday morning and discovered the two dead bodies.
The death of the two officers comes shortly after a series of three suicides by police officers in the Paris area within a few hours on September 22nd.