"Armed robbery on Massena Boulevard in Paris: operation over," police tweeted. "Six people have left. The thief is not on the premises."
Other police sources said seven hostages had been "found safe and sound "after the hold-up at the travel agency in the Chinatown area of southern Paris' 13th arrondissement.
The incident sparked a major police operation in the French capital, where security jitters remain high after a string of terrorist attacks over the last two years, including the November 2015 Paris attacks which left 132 people dead.
Police set up a security perimeter around the Asieland travel agency, which specialises in Asian travel.
Drivers were warned to stay away from the area. Police sources told AFP earlier that the robber was armed with a handgun.
The agency sits in Paris' 13th arrondissement, a residential area that is packed with Asian restaurants and is home to a large Chinese community.
The ground-floor offices sit at the base of a large residential tower block and next to one of Paris' main tram lines.
The robber had attacked the company at around 6:30 pm (1730 GMT), trapping several people inside.
The hostages were let out around two and a half hours later, "their hands on their heads", a police source said, adding that they were "taken into the care of emergency services in a neighbouring building".
Police then searched the building and realised the attacker had fled the scene.
"We saw four or five people coming out with their hands on their heads, followed by around 15 officers," local resident Zinedine told AFP.
"There was no shooting, we heard no explosion. It's over," said the 55-year-old, who had left home to buy cigarettes.
Paris Mayor Anne Hidalgo thanked police for their "speed and professionalism" on Twitter, adding: "I offer all my support to the staff and customers of the agency that were confronted with this criminal act."
The capital is under tight security, with troops patrolling the streets daily, under a state of emergency imposed by President Francois Hollande after last year's Paris attacks.
The hold-up in Chinatown comes at a time of heightened safety concerns among Paris' large Chinese community following a fatal attack on a tailor in August and a series of muggings.
More than 10,000 Chinese Parisians staged a protest march in September calling for increased security for the community following the killing of Zhang Chaolin, beaten to death during a robbery.