Objective:To measure fetal cerebellum volume by using virtual organ computer aided analysis(VOCALTM) of three-dimensional ultrasound. Methods:176 healthy pregnant women with gestational age between 19 to 38 weeks were enrolled in this study. Using two-dimensional mode to find the plane of transverse cerebellum diameter,then changed to the three-dimensional mode.The fetal cerebellum was scaned by three-dimentional ultrasound,and the volume would measured by the program of VOCALTM. Results:The fetal cerebellum volume changed with gestational age. The cerebellum volume increased from 1.258 cm3 at 19 weeks to 18.913 cm3 at 38 weeks in average,R2=0.9938. Conclusion:The fetal cerebellum volume could be measured by virtual organ computer aided analysis of three-dimensional ultrasound. The fetal cerebellum volume changed with the gestational age.