We propose a diaphragm-based optical fiber sensor for pulse wave monitoring. A Fabry-Perot (F-P) cavity composed of a brass diaphragm and fiber end is utilized to form a sensor head. A parallel flat glass and linear charge-coupled device (CCD) are used as an optical demodulator. The mathematical model of optical cross-correlation demodulation is established. In an experiment, the monitoring system enables the real-time measurement of pulse waves from different subjects in different states. The obtained pulse wave, which has distinct feature points, is consistent with classical pulse wave theory. Hence, the research is significant for the development of digital pulse diagnosis technology.