Transferring Window is a device to prevent contamination while transferring items in and out of the purified room condition. This device is an assistant equipment for purified rooms, mainly used for the transfer of small-sized objects between purified areas or between purified and unpurified areas, so as to reduce the number of door opening times and to keep contamination to the lowest possible level for purified rooms, meantime it facilitates the normal condition maintenance of purified rooms. Selectable accessories are electronic linking locks and mechanical linking locks.