The invention relates to a tip-tilt correction system and correction method suitable for an astronomical telescope, and belongs to the technical field of optical engineering. The correction system comprises a first translation platform, a second translation platform, a fast reflecting mirror, a second completely reflecting mirror and a CCD sensor, wherein a first completely reflecting mirror and a reflecting mirror sharing the same optical axis are arranged on the first translation platform, a sampling mirror provided with a central hole and located on an observation star focus is arranged on the second translation platform, the fast reflecting mirror is located above the second translation platform, the second completely reflecting mirror is located below the second translation platform, and the CCD sensor is in communication connection with the fast reflecting mirror. The correction system provided by the invention has two mutually independent companion star sampling optical paths, so that the flexibility is high, the luminous energy information of the two companion star sampling optical paths can be considered by using only one CCD sensor, tip-tilt correction of the fast reflecting mirror is facilitated, and the imaging resolution is improved; and meanwhile the position of the card focus of the astronomical telescope is invariable so as to avoid influence to the positions of other detection equipment.