A light bar fixing structure of a backlight module includes a reverse U-shaped frame, a light bar structure, and a fixing plate. The reverse U-shaped frame, which has an opening and multiple slits therein, is disposed on a back cover of the backlight module. The light bar structure includes a substrate and a plurality of light emitting devices. The fixing plate is attached to the substrate by using an adhesive layer. In addition, a plurality of buckling portions is provided in a periphery of the fixing plate, and by engaging the buckling portions with the slits, the fixing plate is fixed on the reverse U-shaped frame, which makes the light bar structure protrude from the opening of the reverse U-shaped frame after inserting through the opening. Therefore, regardless of light emitting device thickness, the light bar structure can be, in this manner, fixed on the back cover.