A blood pressure data processing apparatus includes: a blood pressure surge acquisition unit configured to acquire a blood pressure surge； a blood pressure waveform extraction unit configured to extract a blood pressure waveform of one or more heartbeats from the blood pressure surge； a waveform feature amount calculation unit configured to calculate a waveform feature amount for each blood pressure waveform of one heartbeat isolated from the blood pressure waveform of one or more heartbeats, or for an average blood pressure waveform obtained by averaging the blood pressure waveforms of one heartbeat isolated from the blood pressure waveform of one or more heartbeats； and a causal factor identification unit configured to identify a causal factor of the blood pressure surge from among predetermined causal factors, based on the waveform feature amount.
