The present invention provides a light-guide-plate (LGP) positioning sheet, which comprises: a fixing portion used to fix the LGP positioning sheet onto a fixing frame of a backlight module, a positioning portion used to abut against and position a light guide plate, and a connecting portion used to connect the fixing portion and the positioning portion. The present invention is further related to a backlight module. According to the LGP positioning sheet and the backlight module of the present invention, the LGP positioning sheet can efficiently ensure the complete alignment between a light emitting diode (LED) light source and a light input side surface of the light guide plate, so as to increase the light utilization rate of the light guide plate.