The invention discloses an agile satellite dynamic imaging posture adjustment method which can achieve wide-width imaging in a posture adjusting process. Firstly, a rolling angle of a satellite is adjusted to achieve push-scan imaging in the east-west direction; then, a pitch angle and pitch angular speed of the satellite are adjusted to compensate transport velocity of rail motion on the earth surface; and finally, a yaw angle of the satellite is adjusted to control a drift angle. The posture adjustment method can be applied to dynamic imaging technique for the satellite to open optical effective load to image in a triaxial attitude maneuver process. The covering power of the satellite in the east-west longitude direction in one-loop transit is improved through real-time posture adjustment. The covering width in the east-west longitude direction can reach more than 350km.