This paper reports the results of evaluation on seismic performance of traditional wooden houses in Seki, where damage caused by future earthquakes is concerned, based on structural investigation. Our conclusions are as follows. a) There are many houses that have complex plan and structure. b) Yield base shear coefficients in ridge direction is small. Moreover, we find houses that falls below the value of 0.1 because the weights of house are heavy and there is no wall adequately in the first floor. c) We confirm termite damages at a rate of around 30 % of the target houses.