At around 3:30 a.m., the men broke into an outlet of chain Vector Takasaki and stole about 50 items, including wristwatches and hand bags.
In security camera footage released by police, one of the thieves can be seen smashing the display cases with a hammer and collecting the merchandise in a cardboard box.
Both perpetrators fled the scene in a vehicle just as police arrived at the scene.
According to police, both men were attired in black trousers and hooded sweatshirts.
Police believe the pair may have been behind a similar burglary of a jewelry shop in Takasaki in July.
