The invention relates to an indirect competition enzyme linked immunoreagent kit for detecting mercury ions and a manufacturing method of the kit. An elisa plate enveloped by mercury ion envelope antigens, mercury-ion-resisting monoclonal antibodies, elisa second antibodies, a substrate color developing solution, a stop solution, a mercury ion standard solution, a washing liquor concentrated solution and a sample treating liquid are arranged in the kit. The kit can detect the mercury irons in a trace mode, is used for detecting the mercury irons in the environment, the soil, water, foods, medicines, cosmetics and the like, and has the advantages of being rapid, easy and convenient to use, sensitive, peculiar, economical and the like. The kit is few in detection step and high in timeliness, saves detection time, reduces operation errors and can perform field detection. The kit is low in requirement for pretreating samples, simple in treatment process, not only can be used for screening the samples in large batch, but also can perform rapid detection on the samples in small batch, and not only provides technical support for environment and food safety, but also provides effective technological means for food import and export inspection, food inspection, monitoring and evaluation of environmental pollution and the like.