The invention discloses an access control system for preventing accidental entry into a charged spacing. The system comprises an entry door and door locks. The door locks comprise a mechanical door lock, an electromagnetic door lock and a control system. The control system comprises a DC control power supply, an access control power supply and a plurality of control loops. The control loops include an anti-short-circuit lock and state release loop, a five-prevention unlocking and electromagnetic lock loop and an access control release loop. The anti-short-circuit lock and state release loop isformed by an electric code lock series connection anti-short-circuit lock relay and is connected to the DC control power supply. The access control release loop comprises an electromagnetic door lockand is connected to the access control power supply. According to the invention, substation operator or construction personnel can be effectively prevented from forcibly entering a charged equipmentspacing to work, the deficiencies of a five prevention system are thoroughly solved, the personal injury and death are effectively prevented, and the safety of persons and equipment is ensured.