To provide a tatami mat with superior repulsion characteristics and prevent the generation of acarine and mold caused by dew condensation by fixing crossing and contact parts of a fiber composed of synthetic fiber by the melting and hardening of binder component.

Crossing and contact parts of a fiber composed of synthetic fiber 1 of fiber length 3-10 mm are fixed by the melting and hardening of fiber- state or powdered binder which melts at a temperature lower than that of the synthetic resin fiber 1 so that a floor material A for a tatami mat to be a molding of a porous structure is provided. The apparent density of the floor material A for the tatami mat is set to 0.4-0.7 g/cm3. The mixing rate of the binder component 2 is preferably set to within the range of 20-60 wt.%. The tatami mat is formed by using synthetic resin tatami facing for the surface of the floor material A for the tatami mat. This constitution can provide the tatami mat having superior repulsion characteristics and preventing the generation of the acarine and the mold caused by dew condensation.