A posture detection method and system are provided. The posture detection method includes: obtaining skeleton data of a target person; analyzing the skeleton data to obtain actual posture information of the target person; and recording the actual posture information of the target person. The accuracy of determining the posture information by obtaining the skeleton data of a body is quite high. Besides, the actual posture information is recorded automatically, so that a doctor does not need to record the posture information manually. Therefore, scanning missing or wrong scanning direction caused by inconformity between the real posture of the patient and the recorded posture information may be avoided, which ensures the reliability of medical diagnosis.