The utility model relates to a low-salt wastewater treatment device. The system comprises a clarification tank and reverse osmosis treatment equipment which are used for treating wastewater and are connected with each other, the clarification tank is arranged at the upstream of the reverse osmosis treatment equipment; an outlet of a dosing pipe used for adding a coagulant into the clarification tank extends into a pipeline used for conveying raw water into the clarification tank; the outlet is connected with a medicine distributor, the medicine distributor comprises a medicine distributing main pipe communicated with the outlet on a liquid path and a plurality of medicine distributing branch pipes connected with the medicine distributing main pipe, and each medicine distributing branch pipe is provided with a plurality of spraying holes for spraying a coagulant. According to the utility model, the flow of raw water can be utilized to reach the clarification tank when the raw water is conveyed by the pipeline, a coagulant is sprayed out from the medicine distribution branch pipe to be fully mixed with the raw water, the subsequent stirring time can be effectively shortened, the pretreatment time is shortened, and the water treatment efficiency is improved.