An injection molding machine capable of opening/closing a movable mold relative to a stationary mold by moving a crosshead backward and forward to move a movable platen backward and forward relative to a stationary platen through a toggle link. The injection molding machine includes a reciprocating mechanism that receives a counterforce exerted on the crosshead in the back-and-forth direction when the movable mold and the stationary mold are closed, and a load acquisition unit that acquires a load exerted on the reciprocating mechanism in a direction perpendicular to the back-and-forth direction of the crosshead.