A system of this invention is directed to a bone cutting support system that properly indicates a bone cutting plane determined in advance to a doctor during surgery. The bone cutting support system includes a storage that stores 3D shape data of a surgery target bone in association with position data of a marker fixed to the surgery target bone, a bone cutting plane determiner that determines, based on the 3D shape data of the surgery target bone, a position and direction of a bone cutting plane or a bone cutting guide plane representing a plane to guide for cutting the surgery target bone, and a bone cutting plane display that displays the determined bone cutting plane based on an image obtained by capturing the marker fixed to the surgery target bone.