Abstract: This paper presents PIV results of turbulent mixing of the cloud and unsaturated air with different environmental humidity in a small cloud chamber (80 ×80 ×100cm3 ).Turbu-lence characteristics such as the variation,skewness and flatness factors of two-dimensional ve-locities are first calculated to demonstrate the anisotropy of such turbulent fields of several centi-meters scale.Experimental results further show that the departure of the probability density function(PDF)of the vertical velocity component from the standard Gaussian distribution be-comes more obvious at the tails with the increase of unsaturated environmental humidity.The anisotropy of the turbulence is further revealed by the difference between the second-order struc-ture functions of two velocity components.The isotropic ratio (the ratio of transverse structure functions to longitudinal structure functions)is far different from the theoretical value for homo-geneous and isotropic turbulence and its dependence on the environmental humidity is complicated and needs further investigation.