High flux research reactors are a type of reactor used primarily as neutron sources. They have higher power density and neutron flux, and their design is very different from that of conventional power reactors. In addition, because research reactors usually use aluminum alloy fuel cladding, in order to reduce cladding corrosion, the coolant usually uses weakly acidic water, which is different from the alkaline water used in conventional pressurized water reactors. Therefore, the water chemical properties and irradiation decomposition of the coolant are different from those of conventional pressurized water reactors. This paper conducts a preliminary study on the irradiation decomposition of the coolant in the high flux research reactor, analyzes the irradiation of gamma and neutrons alone, and the irradiation of gamma and neutrons at the same time, and focuses on the comparative analysis of the concentration of key products, dose rate and pH on the irradiation decomposition of the coolant.