An image forming apparatus comprising a liquid-cooled cooling system (10; 10a) for cooling an image forming portion whose temperature is increased by an image forming operation, using a coolant, the liquid-cooled cooling system (10; 10a) includes: a heat-receiving member disposed in thermal contact with the image forming portion and having a flow path through which the coolant flows; an inlet-side pipe attached to a coolant inlet side of the flow path in the heat-receiving member ; an outlet-side pipe attached to a coolant outlet side of the flow path in the heat-receiving member ; wherein the inlet-side pipe and the outlet-side pipe attached to the heat-receiving member are connected to the tube member via a joint ; a tube member connected between the inlet-side pipe and the outlet-side pipe for forming a circulating path for circulating the coolant through the flow path in the heat-receiving member ; a pump disposed at a point along the tube member for circulating the coolant, wherein the liquid-cooled cooling system (10; 10a) further includes: a radiating unit disposed at another point along the tube member and configured to radiate heat absorbed by the coolant from the image forming portion via the heat-receiving member , wherein the joint is disposed within a space (A) provided between the image forming portion and an electrical component drive portion for driving or controlling the image forming portion , wherein the joint is enclosed by a shielding member (21; 21a, 21b) configured to shield the joint portion from the image forming portion and the electrical component drive portion , characterized in that the joint is enclosed by the shielding member in an airtight manner. a heat-receiving member disposed in thermal contact with the image forming portion and having a flow path through which the coolant flows; an inlet-side pipe attached to a coolant inlet side of the flow path in the heat-receiving member ; an outlet-side pipe attached to a coolant outlet side of the flow path in the heat-receiving member ; wherein the inlet-side pipe and the outlet-side pipe attached to the heat-receiving member are connected to the tube member via a joint ; a tube member connected between the inlet-side pipe and the outlet-side pipe for forming a circulating path for circulating the coolant through the flow path in the heat-receiving member ; a pump disposed at a point along the tube member for circulating the coolant, wherein the liquid-cooled cooling system (10; 10a) further includes: a radiating unit disposed at another point along the tube member and configured to radiate heat absorbed by the coolant from the image forming portion via the heat-receiving member , wherein the joint is disposed within a space (A) provided between the image forming portion and an electrical component drive portion for driving or controlling the image forming portion , wherein the joint is enclosed by a shielding member (21; 21a, 21b) configured to shield the joint portion from the image forming portion and the electrical component drive portion , characterized in that the joint is enclosed by the shielding member in an airtight manner. a radiating unit disposed at another point along the tube member and configured to radiate heat absorbed by the coolant from the image forming portion via the heat-receiving member , wherein the joint is disposed within a space (A) provided between the image forming portion and an electrical component drive portion for driving or controlling the image forming portion , wherein the joint is enclosed by a shielding member (21; 21a, 21b) configured to shield the joint portion from the image forming portion and the electrical component drive portion , characterized in that the joint is enclosed by the shielding member in an airtight manner. <EOS>