The invention discloses a hydraulic brake device. The device comprises a brake band, a fixed base and a driving assembly; the brake band is mounted on the circumference surface of a brake hub and holds the brake hub, the fixed end of the brake band is mounted on the fixed base, the locking end of the brake band is in transmission connection with the driving assembly, the driving assembly is in transmission connection with the locking end of the brake band sequentially through a connecting plate and a locking connecting rod, when the driving assembly acts, the connecting plate is driven to rotate by a certain angle, the connecting plate drives the locking connecting rod to form jacking force for the locking end of the brake band in the circumferential tangent direction of the brake hub, thelocking end of the brake band moves towards the fixed end and presses the brake hub, and brake is achieved; the jacking force of the locking connecting rod for the locking end in the brake process isalways in the circumference tangent direction of the brake hub, the locking end is always attached to the brake hub, the maximum design wrap angle of the brake device can reach 340 degrees, and meanwhile, the problem that in the prior art, in the brake process of a band type brake, the actual wrap angle of the brake band becomes small can be solved.