Abstract: A mixing valve apparatus is disclosed, for producing a mixed fluid of a desired temperature obtained by mixing high temperature fluid and low temperature fluid with each other. The apparatus includes a pressure-sensitive control unit (6) which operates in response to the differential pressure (.DELTA.P) between the inlet pressure of the low temperature fluid and the pressure of the mixed fluid, and which unit controls the opening degree of an inlet valve (V.sub.1) for the high temperature fluid. Pilot passage (R.sub.0 .about.R.sub.3) for communicating the inlet pressure of the low temperature fluid to said unit is provided with a throttle (L, L.sub.1) whose effective surface area varies in response to the temperature of the mixed fluid, to compensate the opening degree of the inlet valve (V.sub.1) for the high temperature fluid upon variation of the temperature of the mixed fluid.