为了准确有效地完成经纬仪航向标定，本文根据标校经纬仪坞内航向标校原理，分析了各单项误差对航向标定的影响，建立了照准差和定向误差同时影响下的航向标定修正模型，给出了具体的修正方法。实验及检测结果表明，用正倒镜法测得的定向误差数值等于定向误差与照准差的差值。文章验证了修正方法的正确性和有效性，规范了坞内航向标定方法，为测量船完成测量任务奠定了基础。

To precisely and effectively complete the heading calibration of a theodolite, this paper analyzes the effect of single error on the heading calibration, and builds a correct model of the heading calibration when the collimating and orientation errors are involved at the same time according to the heading calibration principle. It provides the specific correction and verification methods. Experimental and measurement results indicate that the orientation error measured by positive and inverse pointing methods is equivalent to the error between orientation error and collimating error. The research in this paper proves the feasibility and effectiveness of the correction method and disciplines the method of heading calibration at the dock, which will make sure TT&C complete mission successfully.