Hsueh and O Brien (1971) proposed a model on coastal upwelling induced by alongshore current. Their model is two - dimensional .steady , f - plane , linear and homogeneous with constant depth , in which wind effect was not considered . In the present paper, we proposed a steady model on upwelling in a strait with alongshore boundary current and wind applied on the surface. The following conclusions have been drawn.1 . Alongshore boundary current contributes more to upwelling than wind near the right coast.2. Alongshore boundary current influence can reach to about 70 km away from the right coast.3. Upwelling in the left half of the strait is mainly produced by wind .4. Under certain conditions, the combined action of wind and alongshore boundary current can produce upwelling in the middle of the strait. Hsueh and O Brien (1971) proposed a model on coastal upwelling induced by alongshore current. Their model is two - dimensional .steady, f - plane, linear and homogeneous with constant depth, in which wind effect was not considered. , along following the boundary current current and wind applied on the surface. The following conclusions have been drawn.1. Alongshore boundary current contributes more to upwelling than wind near the right coast.2. influence can reach to about 70 km away from the right coast.3. Upwelling in the left half of the strait is mainly produced by wind. 4. Under certain conditions, the combined action of wind and alongshore boundary current can produce upwelling in the middle of the strait.