Abstract: In this aztide, the characteristic values of cross-section mean vozticity is chosen as the useful physical variable to evaluate the hydraulic conditions in the Chinese sturgeon habitat.The computing methods for the cross-section mean vozticity are developed.The distribution of mean vozticity is computed along Chinese sturgeon spawn field based on the field measured data.The range of vozticity strength is about 0.27/s to 0.85/s, but Chinese sturgeon spawns are distributed mainly over the area where the vozticity strength is larger than 0.4/s.It means that the Chinese sturgeon prefers in the water area with larger vozticity strength of cross-section in order to increase their fertilization rate.