Daily activities. especially for the elbow amputation, it causes severe damage to the movement of the hand for different common purpose. the available prosthetic elbow and disarticulation prosthesis are very costly and cannot be afforded by the common and economical backward people in india. by realizing the extreme requirement of elbow amputee people usability and affordability, the design and development of is carried out for interlock mechanism based bio-compatible, user-friendly and costeffective elbow disarticulation prosthesis. there is no complicated electronic and motorized actuation involved in this which makes this design simple. this design incorporates the internal slot mechanism which will provide an adequate motion of the artificial hand connected to the elbow joint. the joint is developed mechanically which helps the prosthesis to bring back sound gait of elbow and hand similar to normal elbow. the design is very compact and not exposed outside of the hand so that normal clothing for the patient is not hampered. the design of elbow joint incorporates simple machining and manufacturing process for easy fabricated. most importantly, the cost of the prosthetic joint is around rs. 1500-2000/unit by machining of single unit. however, the cost can be further reduced by mass production. since the innovation is focused on the mechanical linkage based low cost prosthesis, this innovation will certainly helps the elbow amputee people to bring back their normal hand gait cycle. commercialization of this innovation is going to serve majority of the elbow amputees. as the development is carried out for a very unique group of specially-abled people, certainly implementation of which have positive impact on the society.