There are axis errors in orientation processing of a digital zenith camera. This paper focuses on how to compensate the axis errors among optical axis, rotation axis and vertical axis. To calculate the astronomical coordinate of the vertical axis in a measuring station position, two star images in an opposite direction were used to calculate the coordinate of the rotation axis. Thus, the compensation between optical axis and rotation axis was avoided. A two-axis tilt sensor was used to measure the inclination between rotation axis and vertical axis and the position coordinate of the vertical axis could be obtained by compensating the angle error of the rotation axis. As the turntable error could impact on the coordinate of rotation axis and tilt compensation, the influences of turntable error on the calculation of rotation axis and tilt compensation were analyzed, respectively and the range of turntable error was gained. The experimental data demonstrate that when the absolute value of the latitude of the measuring station is below 88.3°, the turntable should be below 35″. Otherwise, the turntable error should be below |1 166.8cosδ|″. The precision of rotation angle should be improved to eliminate the influence of turntable error when the coordinate of the measuring station is calculated in the opposite direction.