Abstract: A precise and rapid positioning mechanism for stencil printing comprising a stencil, a carrier, a plurality of pins, and a plurality of positioning pins. There are a plurality of same sized pin eyes formed on both the stencil and the carrier respectively at positions facing against each other for interposing the pins therebetween to set the stencil and the carrier. Next, raising the positioning pins by air cylinder supplied from the carrier so as to fit setting holes on the substrate into the corresponding positioning pins thereby firmly securing the substrate. Then afterwards, by imbibing the substrate with vacuum evacuation force from the carrier so as to put down the positioning pins thereby attaching the stencil together with the substrate and trans-printing a desired pattern on the substrate.