Mechanical chain transfer window is an auxiliary equipment for clean rooms, mainly used for the transfer of small items between clean areas and between clean areas, and between clean areas and non clean areas, in order to reduce the number of clean room doors and minimize pollution to the clean room. The transfer window is made of stainless steel plate, which is flat and smooth. The two doors are interlocked to effectively prevent cross contamination, equipped with electronic or mechanical interlocking devices and equipped with ultraviolet sterilization lamps.