The invention relates to a quasi-phase super-resolution circuit of thoracoabdominal surface respiratory movement signals, and belongs to the technical fields of precision instruments and thoracoabdominal radiotherapy. The circuit comprises a signal conversion module, a phase difference multiple output module, a resistor chain multiphase generation module, a multiphase sinusoidal square wave conversion module and a multiphase fusion logic gate module; the modules are indispensable as a whole, and convert the respiratory movement signals of one cycle into quasi-phase square wave signals of multiple cycles jointly, and the null cycle of the signals is output by a super-resolution square wave with phase difference of a quasi phase; that is to say, super resolution of the thoracoabdominal surface respiratory movement signals is achieved, and further technical advantages which can be brought by the result are that in a process of multiple respiratory cycles, by judging frequency change of square wave signals, change of the respiratory frequency can be judged, and more importantly, due to the fact that the cycle of the super-resolution square wave is much smaller than the respiratory movement cycle, change of the respiratory frequency can be judged in a time range smaller than one respiratory cycle.