Abstract: A gait monitoring and healthcare system includes a first IMU, a second IMU and a local host. The first IMU senses an activity state of a thigh and generates a first activity signal. The second IMU senses an activity state of a calf and generates a second activity signal. The local host includes a microprocessor and an alarm. The microprocessor performs operations of: calculating a first pitch angle between a horizontal plane and the first IMU, and a second pitch angle between the horizontal plane and the second IMU according to the first and second activity signals; calculating activity information of a knee joint, including a bending angle, according to the first and second pitch angles; and judging whether the bending angle of the knee joint falls within a dangerous range according to the activity information, and controlling the alarm to output a warning signal if yes.