Compact water-cooled capacitor

The utility model discloses a compact water-cooled capacitor, which comprises an outer shell, a first end cover, a second end cover, an electrode ring group and a cooling disc, wherein the first end cover and the second end cover are respectively arranged at the upper end and the lower end of the outer shell; the first end cover and/or the second end cover are/is located at the outer end part and are/is concavely provided with an annular mounting groove towards the axis around the periphery, the cooling disc is contained in the annular mounting groove and forms an annular water circulation channel in a surrounding manner, and the cooling disc is provided with a water inlet and a water outlet which are communicated with the water circulation channel. According to the compact water-cooled capacitor, the space structure of the capacitor is fully utilized, water circulation cooling is achieved without increasing the size of the capacitor, a user can use the capacitor in an original matching box, more installation