Abstract: The present invention relates to a microfluid device for discharging a fluid or a mixture of fluids including a discharge channel, at least one main fluid supply channel which leads into at least one secondary supply channel which is essentially situated in the same plane as the discharge channel, and which leads laterally towards the discharge channel and, in turn, leads into an inlet channel situated above or below the discharge channel, the inlet channel entering into the discharge channel from its top or bottom side via at least one inlet opening. The at least one inlet channel has a cross-sectional shape which changes in the longitudinal direction and/or in that the at least one inlet opening has an opening width changing in the transverse direction of the discharge channel.