A femoral component trial for a knee joint of the present invention includes a trial body. The trial body includes a medial condyle and a lateral condyle that are located away from each other on an external surface, a through hole that is located between the medial condyle and the lateral condyle and has an approximately rectangular shape whose long side is an outer edge of an inner wall located along a back-and-forth direction and whose short side is an outer edge of an inner wall located along a right-and-left direction in an external surface view, a first guide slit that is located ahead of and above the through hole and extends in the right-and-left direction, and four second guide slits respectively extending from four corner parts of the through hole and along the long side.
