The invention discloses a method for calibrating the constant drift of a gyroscope combination. The method comprises the steps of collecting measured values of three orthogonal gyroscope meters of the gyroscope combination; acquiring the constant drift of the three orthogonal gyroscope meters of the gyroscope combination according to a relationship between the measured values of the three orthogonal gyroscope meters of the gyroscope combination and the earth rotation speed. The method provided by the invention does not strictly require the relationship between the earth rotation speed and the placement of the gyroscope combination, does not need professional and precise technological equipment to determine the component value of the earth rotation speed on a sensitive axis of the tested gyroscope meter, and is less in requirements for test guarantee conditions. The method is beneficial to convenient and fast calibration of constant drift parameters under the condition of a satellite control system or a whole-satellite test after the gyroscope combination is delivered, thus avoiding the change of the parameters of the gyroscope combination with a lower constant drift repeatability index after zero-order energization is performed or when the gyroscope combination accesses the control system after the measurement of the constant drift on special process equipment; therefore, the method is especially suitable for simple and convenient measurement of the gyroscope combination after the gyroscope combination is delivered to the satellite control system or is loaded in a satellite.