The invention discloses a single-manipulator automatic ultrasonic non-destructive detection device which comprises the following components of an industrial control machine, a manipulator device, an ultrasonic transmitter-receiver set, a water coupling device and an auxiliary device, wherein the manipulator device comprises a joint-type six-degree-of-freedom manipulator, a manipulator controller, a power supply and a signal integrated wire cable; the ultrasonic transmitter-receiver set comprises a phased array ultrasonic transducer, an ultrasonic pulse transmitter-receiver card and a high-speed data collecting card; the water coupling device comprises a water spraying nozzle, a pressure stabilizing and flow stabilizing water pump and a flexible guide pipe; and the auxiliary device comprises a camera, a monitor, an adjustable workpiece support and a water recycling groove. The device is suitable for ultrasonic reflection method detection of workpiece thin layer and front surface; compared with the traditional device, the device can implement automatic ultrasonic detection of complex and irregular curve surfaces, has high detection efficiency, has very wide part adaptability and system flexibility, and has wide industrial application prospect.