Provided is a solution mixture injector capable of adjusting the amount of a second liquid introduced to a main channel when the water pressure in the main channel has increased or decreased. A solution mixture injector having an injection port (6) for jetting water to the distal end of a main channel (5) through which passes water fed from a water supply apparatus, the injector being provided with a solution tank (10) for holding a second liquid other than water, and a solution channel (11c) for introducing the second liquid from the solution tank (10) into the main channel (5), wherein the solution mixture injector is further provided with a branch channel (13) that branches from the main channel (5) further upstream from the merging part with solution channel (11c), a water tank (15) formed at the terminal end of the branch channel (13) and used for holding water, and an air channel (17) for interconnecting the interior of the water tank (15) and the interior of the solution tank (10) to ventilate the water tank and the solution tank. The volume of water in the water tank (15) is adjusted by varying the water pressure and/or the flow rate in the main channel (5), and a force for compressing the second liquid in the solution tank (10) on the main channel (5) side is adjusted via air in the air channel (17).Linvention porte sur un injecteur de mélange de solution, lequel injecteur est apte à ajuster la quantité dun second liquide introduit dans un canal principal quand la pression deau dans le canal principal a augmenté ou a diminué. Un injecteur de mélange de solution présente un orifice dinjection (6) pour éjecter de leau vers lextrémité distale dun canal principal (5) à travers lequel passe de leau acheminée à partir dun appareil dalimentation en eau, linjecteur comportant un réservoir de solution (10) pour contenir un second liquide autre que de leau, et un canal de solution (11c) pour introduire le second liquide à partir du réservoir de solution (10) dans le
