A technique for feature point extraction of human body based on image was presented to solve the problem of body feature parameter extraction in threedimensional human body modeling. Then each part of the human body in picture was distinguished, and the calculating process was given. First, the collected image was preprocessed, and then the front and side body feature points were identified to get body feature district, finally, the body feature sizes were extracted. The method to calculate the body feature sizes was introduced according to the modeling method and the reference method. Then a new method was proposed to improve the accuracy of body feature sizes. Human body feature parameters were obtained from the collected images by the modeling reference method. Results show that the method can accurately extract the feature points and the feature sizes.