To provide a means enabling a user to place tatami mats on the floor of a building of a gymnasium, an auditorium or the like, not usually used as dojos, to simply build a martial-arts hall capable of being used for a game or a competition of the martial arts such as judo and to easily disassemble and remove them after the use.

The tatami mat setting frame consists of an edge part and a tatami mat insertion part and has an anti-slip means on the bottom. The edge part is linearly formed. The tatami mat insertion part, formed into a plane extending from the lower part of the edge part to a side and inserted under juncture of the tatami mats in the use, is made of a material such as rubber having a damping function.