The invention discloses a movable protection platform for constructing a bridge. The movable protection platform is characterized in that a suspension trolley (2) is connected onto a truss structure (1) and is connected with a track at the bottom of the bridge; a steel wire rope net (6) is arranged at the bottom of the truss structure (1); and protecting railings (4) are arranged around the truss structure (1). The movable protection platform disclosed by the invention has the advantages that firstly, an operation platform is provided for the operation process by constructors at the bottom of the bridge and the construction of the bridge is facilitated; and secondly, the movable protecting platform comprehensively covers the whole construction area; and the constructors accidently fall in the construction process and fall on the protecting platform, and thus the life safety of the constructors is ensured. The movable protection platform disclosed by the invention can be synchronously pushed ahead along with the construction of the bridge in the construction process and has the characteristics of power drive, simplicity in locking, convenience in operation, acceleration of work period, safe guarantee and the like.