An injection molding machine comprising: a movable platen; a rear platen; and a link mechanism which has a plurality of links (151, 152, 153, 154), one end connected to the movable platen, and the other end connected to the rear platen, wherein at least one connection portion of a connection portion which connects the movable platen and the link (151, 152, 153, 154) to each other, a connection portion which connects the links (151, 152, 153, 154) to each other, and a connection portion which connects the rear platen and the link (151, 152, 153, 154) to each other, includes a bush, a connection pin which is inserted into the bush, and a supply path (62, 63) through which a lubricant is supplied to a bearing clearance which is a clearance between the bush and the connection pin, and wherein the injection molding machine further comprises: a lubrication state determination unit which is configured to determine a lubrication state between the bush and the connection pin, and an electrical resistance detection unit which is configured to detect, an electric resistance between the bush and the connection pin, characterized in that the link mechanism is a mechanism which causes a first mold to move close to or away from a second mold in a direction of the second mold to perform mold closing, mold clamping, and mold opening, and the lubrication state determination unit is configured to determine the lubrication state between the bush and the connection pin based on the electric resistance detected by the electrical resistance detection unit in a state where the first mold and the second mold are separated from each other. a movable platen; a rear platen; and a link mechanism which has a plurality of links (151, 152, 153, 154), one end connected to the movable platen, and the other end connected to the rear platen, wherein at least one connection portion of a connection portion which connects the movable platen and the link (151, 152, 153, 154) to each other, a connection portion which connects the links (151, 152, 153, 154) to each other, and a connection portion which connects the rear platen and the link (151, 152, 153, 154) to each other, includes a bush, a connection pin which is inserted into the bush, and a supply path (62, 63) through which a lubricant is supplied to a bearing clearance which is a clearance between the bush and the connection pin, and a bush, a connection pin which is inserted into the bush, and a supply path (62, 63) through which a lubricant is supplied to a bearing clearance which is a clearance between the bush and the connection pin, and wherein the injection molding machine further comprises: a lubrication state determination unit which is configured to determine a lubrication state between the bush and the connection pin, and an electrical resistance detection unit which is configured to detect, an electric resistance between the bush and the connection pin, a lubrication state determination unit which is configured to determine a lubrication state between the bush and the connection pin, and an electrical resistance detection unit which is configured to detect, an electric resistance between the bush and the connection pin, characterized in that the link mechanism is a mechanism which causes a first mold to move close to or away from a second mold in a direction of the second mold to perform mold closing, mold clamping, and mold opening, and the lubrication state determination unit is configured to determine the lubrication state between the bush and the connection pin based on the electric resistance detected by the electrical resistance detection unit in a state where the first mold and the second mold are separated from each other.