Two masked gunmen forced their way into the closed Apple Store in the Opera district near the Galeries Lafayette department store through a back door around 8:50 p.m. New Year's Eve, while two other men waited outside in a van, police said.
A janitor in the store, which closed at 6 p.m., was slightly injured, French newspaper Le Monde reported.
The burglars walked past the display cases filled with Apple products and went straight to the storeroom filled with boxed products, police said.
They loaded hundreds of boxes into the van, which took off with all four men 50 minutes later, police said.
The robbery was the biggest and best-organized theft of a Paris Apple Store, several news organizations said, as well as the first one involving guns.
Police said they were checking security-camera videos as part of their investigation.
They would not confirm French and British media reports estimating the loss from the robbery at around $1.3 million. Police said the store manager was still tallying the loss.
Apple headquarters in Cupertino, Calif., did not immediately return a phone call and email from United Press International seeking comment.
"They prepared their coup pretty well," French police union official Christophe Crepin told reporters, explaining the store was located near large boulevards that lead to several different parts of the city.
He and other police officials said they thought the heist was coordinated to take place while police dealt with large crowds building up for New Year Eve celebrations on the Champs-Elysees and by the Eiffel Tower.
The store was closed Tuesday but appeared intact, Le Monde said.