The invention discloses a breeding water body total hardness detection kit, which contains a total hardness test reagent I, a total hardness test reagent II, two bottles of total hardness test reagentIII and a colorimetric bottle, wherein the test reagents I, II and III comprise disodium ethylenediaminetetraacetate, eriochrome black T, ammonium chloride, ammonia water, a synergist, a masking agent, absolute ethanol and distilled water. According to the present invention, the kit has advantages of rapidness, sensitivity, convenient use, obvious reaction, stable quality and the like, can overcome the problems of reagent deterioration, reagent color changing and the like of the common kit during the detection due to the complex operation steps or the long placing time, further has advantagesof simple and efficient operation steps, significant color change reaction and no requirement of the additional equipment, and is suitable for the on-site rapid detection of a variety of water qualities.