The present invention provides a cover plate structure of ratchet wrench comprising: a main body, inside a head portion thereof has an accommodating space, a peripheral wall is formed in the accommodating space, and the accommodating space is formed with at least one opening; a ratchet mechanism provided in the accommodating space; a cover plate having a cover portion and a snap-abut portion, the cover plate is placed in the opening of the accommodating space, and the snap-abut portion is stuck against the peripheral wall of the accommodating space. an elastic fastener member is disposed between the head portion and the cover plate, the fastener member applies an elastic force to the cover plate, so that the snap-abut portion of the cover plate elastically snaps against the peripheral wall of the accommodating space. The cover plate is capable of bearing the load during operation, increasing the withstand strength of the head portion.