An online load detection device for a self-balancing two-wheel vehicle, comprising a support platform load detection device: the support platform load detection device comprises at least a group of magnetic detection devices; each group of magnetic detection devices comprise a permanent magnet and a magnetic sensor; the permanent magnet is supported on a support platform via an elastic member; the magnetic sensor is disposed in the easing of the support platform, and is used to detect the magnetic field change caused by the relative displacement between the permanent magnet and the magnetic sensor and output a detection signal. The detection device further comprises a seat pressure sensor disposed on a seat. The detection device detects the load pressure of the support platform in a non-contact manner, and can avoid wear, judge and warn the driving attitude of a driver.