Abstract: Based on data of wind speeds in shelterbelt during summer typhoon season in Nanhui and winter season in Jiading, the shelterbelt effects were analyzed. The results showed that the windbreak effect was very remarkable both in summer and in winter. During summer typhoon season, the nearer to the shelterbelt it was, the bigger the windbreak effect was. Along with altitude increase the windbreak effect minished in the near of the shelterbelt, while the windbreak effect increased in far shelterbelt. The windbreak effect of the shelterbelt was related to the wind speeds. The smaller the wind speeds were, the more evident the windbreak effect was. The windbreak effect in two sites got same results in in winter due to the cross of the two shelterbelts. The results would offer reference for distribution of the forest

Key words: Shanghai suburb, Shanghai suburb, Shelterbelt, Windbreak effect