The present invention relates to an underwear-based body data monitoring method and device. The method includes: receiving position data disposed on underwear and respiration data disposed on underwear； calculating displacement, velocity and acceleration； determining whether the displacement, velocity and acceleration all exceed a preset threshold； further determining whether the respiration data is within a preset respiration range when the displacement, velocity and acceleration all exceed a preset threshold； and outputting alarm information when the respiration data is not within a preset respiration range. By the underwear-based body data monitoring method and device, body data can be collected by sensors disposed on underwear in real time. In addition, it is able to roughly determine whether the physical condition is abnormal by the displacement, velocity and acceleration, and then further determine the physical condition by respiration data. The analysis process is simple and the analysis result is accurate and reliable.
