Optical fiber gyro scale coefficient error determining method

The invention belongs to an error determining method, and particularly relates to an optical fiber gyro scale coefficient error determining method. The method includes the steps: step 1, initializing, mounting an inertial navigation system, rotating, and recording a course angle, an attitude angle and a gyro temperature outputted by the inertial system; step 2, calibrating, heating up, rotating for 360 DEG, recording a course angle, an attitude angle and a gyro temperature; and repeating the process until the system temperature rises up to a working temperature upper limit; and step 3, processing the data, dividing a navigation angle difference by 360 DEG, and thus obtaining a scale coefficient error at the corresponding temperature; and by using a fourth-order polynomial model, fitting a change rule between the gyro scale coefficient error and the temperature. The optical fiber gyro scale coefficient error determining method has the effects of high precision and low calibration work amount.