A preferred embodiment of the MEMS cooling device of the invention comprises one or more MEMS micro-channel volumes in communication with one or more MEMS micro-pump assemblies wherein each micro-pump assembly comprises a flexure valve, such as a leaf valve and means to drive a coolant through the channel volumes such as an electrostatic interleaved comb drive structure. A preferred embodiment comprises an inlet micro-pump assembly and an outlet micro-pump assembly but the device may also be fabricated with a single pump mechanism per channel volume.