The invention discloses the field of building construction and particularly relates to a novel column joint operation platform and a mounting method thereof. The novel column joint operation platform comprises a column body and an operation platform body, vertical T-shaped plates are evenly distributed around the column body, two vertical sliding grooves are constituted between each T-shaped plate and the outer surface of the column body, sliding rails are formed at the bottoms of the operation platform body, U-shaped plates matched with the sliding grooves are slidably arranged on the sliding rails, and the open ends of the U-shaped plates are inserted into the sliding grooves. The novel column joint operation platform is reasonable in structure, convenient to mount, safe and reliable.