Provided is a microfluidic device to more easily and effectively operate a valve by improving the structure of valves for controlling a fluid flow more simply and efficiently, which comprises a platform having at least one chamber, at least one flow channel connected to the chambers and transfer fluid, and a valve which opens or closes the flow channel, wherein the valve comprises a body installed in the platform, a blocking plate installed in the body and positioned to face the flow channel to selectively blocks the flow channel, a pressing rod installed to be movable at the inside of the body to press the blocking plate, and a fixing unit installed at the body and fix the pressing rod at a blocking plate pressing position.