To provide an apparatus for micro-fluid mixing enabling quantitative mixing by providing one valve mechanism as a liquid feed mechanism for achieving space-saving.

The apparatus 1 for micro-fluid mixing sequentially feeds a plurality of fluids to a mixing channel using a valve 8, and has a plurality of injection channels 3, 5 injecting the plurality of fluids to the valve; the movable valve 8 having a plurality of passing-through channels containing the plurality of fluids injected from the injection channels; a pressurizing channel 4 provided in contact with the valve and transferring the fluids contained in the passing-through channels to the outside by pressurizing; the mixing channel containing and mixing the plurality of fluids transferred from the passing-through channels by pressurizing of the pressurizing channel; and a valve moving means 11 for, by moving the valve, sequentially feeding the plurality of fluids contained in the plurality of the passing-through channels to the mixing channel by pressurizing.