The present invention discloses a tibia impacter provided with an alignment guide function that helps an artificial tibia implant to be adjusted to the level condition when bone cement is applied to the top surface of the cut tibia and an artificial tibia implant is driven in and fixed. The tibia impacter comprises a guide bar which is installed vertically on one side of the tibia impacter for comparison with the mechanical axis of the tibia to compare the mechanical axis of the tibia and the guide bar, so that the level condition of the artificial tibia implant mounted on the top surface of tibia can be confirmed.