We present a new method to estimate the pose of human head from a monocular image in this paper. The method only uses a face model that formed by five points (four eye-corners and subnasale) in human face, does not need any auxiliary equipment. The estimation involves the research result of the anthropometry in the Mongolian race's feature we had obtained, and employs the theory of the projective geometry. We divide the pose computation into separate estimation of the orientation about X, Y and Z-axis, respectively. For the automatic detection of these points, Active Appearance Models (AAM) is utilized in our experiment. It had been shown that the results of experiment were very close with actual rotational angles of human face. Especially when facial rotation in a naturally small angle, less than 30?, we can obtain the approximate accurate value of rotational angles by using this method.