Observational data from Beijing 325 m meteorological tower are used to investigate the turbulence characteristics in the urban surface layer. The turbulent variances at three levels of 47 m, 140 m and 280 m heights are analyzed in the frame of the local similarity theory. The results show that the variances of wind velocity and temperature can be quite well described by the local similarity theory. However, the comparison shows that the turbulence characteristics at 140 m and 280 m heights are close to each other, while the turbulence characteristics at 47 m height are different from them. These results indicate that, since the turbulence properties in the roughness sublayer are strongly influenced by the dynamical and thermal heterogeneity of urban canopy, they are different to those in the inertial sublayer. And the turbulence statistics in the roughness sublayer and the inertial sublayer should be described by the different schemes.