To improve the measurement for gun rotated accuracy, the measurement error and the method to control the error for measuring the gun rotated accuracy by two theodolite intersection were researched. First, according to the principle of two theodolites intersection measurement, a space calculation model for measuring the gun rotated accuracy was established. Then the factors influencing the measurement error were quantitatively analyzed by the DT202C electronic theodolite, and the measurement error model was established. Finally, the idiographic realization method for the theodolite optimal disposition to control the measurement error was researched after predefining two markers on the gun tube, and the optimal disposition place was calculated by genetic algorithm. The theoretical calculation and the test results indicate that the measuring error of the gun rotated accuracy can be controlled within 0.20 mil by the reasonable disposition of the theodolites. It can meet the test requirements and can remove the uncertainty brought by the stochastic disposition of the theodolite.