The invention discloses an error parameter calibration method and device. The method comprises: establishing a state equation and a measurement equation of an aircraft navigation system, wherein both the state equation and the measurement equation comprise an error parameter vector, and the error parameter vector is formed by a plurality of error parameters; judging observability of each error parameter; when observable error parameters exist, by using a preset duration as a filtering period and utilizing Kalman filtering or adaptive filtering, calibrating out the observable error parameters. The error parameter calibration method and device disclosed by the invention fulfill the aim of calibrating out the error parameters of a guidance tool in real time in orbit.