Heat exchanger and gas water heater

The utility model belongs to the technical field of water heaters, and particularly relates to a heat exchanger and a gas water heater. The heat exchange shell aims at solving the problems that an existing heat exchange shell is low in structural strength and prone to deformation, and consequently smoke leaks. According to the gas water heater, the end plate assembly of the heat exchanger comprises the two-layer structure of the inner end plate and the outer end plate, the structural strength is high, deformation is not likely to happen, the sealing performance of the heat exchanger can be improved, and smoke leakage is avoided. Moreover, the inner end plate forms sealing between the sealing ring and the heat exchange pipeline, so that the sealing performance is improved, a fixing structure and a sealing structure do not need to be additionally arranged, and the structure of the heat exchanger is simplified; the height of the inner end plate in the vertical direction is lower than that of the outer end plate