PURPOSE: To provide an auxiliary brake combined type brake device devised to secure braking force as a cutoff valve and certainly works even at the time when an exhaust valve has a trouble.

CONSTITUTION: An input port 51 is formed on the upper end part of a valve housing 50, a control port 52 and an output port 53 are formed on the side surface and an exhaust port 54 is formed on the lower end part. The control port 52 is connected to a brake valve through an air piping 48, the input port 51 to an air master through an air piping 44 and the output port 53 to an exhaust valve through an air piping 45. In the valve housing 50, a control piston 56 and a valve body 57 are arranged, and a return spring 58 to energize the control piston 56 upward and a return spring 59 to energize the valve body 57 dowanward are provided. A seat surface 60 with which the valve body 57 makes contact is formed on a communicating part of the input port 51 and the output port 53, and a communicating hole 61 communicated to the exhaust port 54 is formed on the control piston 56.