Abstract: The gyrotheodolite is a kind of orientation instrument commonly used for determining the azimuth angle relative to the local North．In the AIT process of Tiangong-I target spacecraft, it is required to determine the attitude of two devices at operation platforms of different heights. On that condition, two theodolites may be blocked due to alignment between each other, thus it is unable to set up the relationship between the datum cube mirrors. To solve that problem, the geodetic coordinates are used as a transfer coordinate system to obtain the angle relationships. This new method for gyrotheodolite measurement is shown to be feasible with a satisfactory error analysis result, which can be used for similar precision measurements of large spacecraft.