A beam direction module which can be applied to an optical switch, comprising: a collimator support member; a first mirror substrate including first micro-mirrors, and first windows through which beams can pass; a first electrode substrate including first mirror driving electrodes, and second windows through which beams can pass; a first spacer; a second mirror substrate including second micro-mirrors, and third windows through which beams can pass; a second electrode substrate including second mirror driving electrodes, and fourth windows through which beams can pass; a second spacer; and an inter-mirror spacer, wherein the first electrode substrate, the first spacer, the first mirror substrate, the inter-mirror spacer, the second mirror substrate, the second spacer and the second electrode substrate are stacked successively on the collimator support member and fixed between caps and the collimator support member while pins protruding from the collimator support member are inserted into alignment through-holes formed.