Skiing, which during wintertime provide jobs at snow-isolated villages, contributes a lot to economy in snowy mountainous areas. But possible climate warming overshadows its future. It is required beforehand to assess the possible decrease in number of skiers, and its impact on local economy taking the so-called multiplier impacts into consideration. For this purpose, we tried input-output analysis on Yamanashi prefecture. Firstly, we estimated the exogenous expenditure paid by skiers. Secondly, we attributed portions for different tourism-related industrial sectors skiers consulting a report. Thirdly, we calculated the multiplier impact. Against our anticipation, indirect impact came in minus. We estimated the total size of the skiers' direct expenditure as 27.8 billion yen in 1994.