There was a fire spreading disaster for 18 wooden houses in the historical townscape formation district in a famous spa resort area. In this paper, a fire spreading analysis of a group of wooden houses was carried out under some conditions of wind velocity and direction in order to numerically simulate a fire spreading phenomenon in the spa resort area and also investigate some fire spreading countermeasures for a group of wooden houses and also investigate an appropriate countermeasure for the fire spreading disaster of wooden houses using both fireproof wall and quasi-fireproof wall on wooden houses. As a result, it should be noted that the installation of fireproof wooden wall in every third wooden house can economically reduce a fire spreading area in comparison with the installation of quasi-fireproof wooden wall in every other wooden house.