The application provides a unilateral nail holder, including: a holding rod having a lower end provided with a clamping groove for receiving a single side plate of a pedicle screw; a fixing hook connected to the holding rod, where the fixing hook is located at an inner rear side of the clamping groove, a rear side of the single side plate is provided with a fixing hole, and the fixing hook hookable with the fixing hole; and a separating mechanism provided between the holding rod and the fixing hook for pushing the fixing hook to withdraw from the fixing hole. The fixing hook is hooked with the fixing hole on the rear side of the single side plate, the single side plate is limited in the clamping groove, and the clamping of the pedicle screw is realized.