The utility model relates to a front curvature angle detection device of a back, which comprises: at least one first detection device positioned at the front of a rider's upper body； at least one second detection device arranged at a fixed position of a moving device controlled by the rider； the first detection device is electrically coupled with the second detection device, and the second detection device acquires the signal of the first detection device and generates a rider's back. The angle of the front of the back.When the anteversion angle of the rider's back is out of the range of the preset anteversion angle, the second detection device will send a warning message to remind the rider to correct the anteversion angle of the back.一種腰背前曲角度偵測裝置，包括：定位於一騎者之上半身前部的至少一第一偵測裝置；設置於該騎者所控制的一運動裝置之固定位置的至少一第二偵測裝置；該第一偵測裝置與該第二偵測裝置電性耦合，該第二偵測裝置獲取該第一偵測裝置的訊號並產生一騎者腰背前曲角度。當該騎者腰背前曲角度脫離預設腰背前曲角度範圍值時，該第二偵測裝置發出一提醒訊息，以提醒騎者修正腰背前曲角度。
