A blood pressure measuring apparatus (1) includes a pressure control unit (3) that controls an applied pressure applied to a region of a living body in which a vein and artery exist by a cuff (2) mountable to the region, a detection unit (4) that detects pressure waveforms in which pulse wave components from the region overlap with the applied pressure, and an analysis unit (5) that obtains a respiratory variation on the waveform of artery and a venous pressure based on the pressure waveforms detected by the detection unit (4) through one-time blood pressure measurement. The analysis unit (5) obtains the respiratory variation on the waveform of artery based on data of a first pressure waveform in a first process, and the venous pressure based on data of a second pressure waveform in a second process and the data of the first pressure waveform.