Provided are a light guide structure (10), a backlight module (20) and a display device, which can reduce a light loss during propagation and improve light utilization efficiency. The light guide structure (10) comprises: a light guide plate (1), the light guide plate (1) comprising an out-light surface (11) and a reflecting surface (12) oppositely arranged, and a side surface (13) connecting the out-light surface (11) and the reflecting surface (12), wherein the material of the light guide plate (1) is an isotropic material; a reflective brightness enhancement film (2), the reflective brightness enhancement film (2) being arranged on the side where the light-emitting surface (11) of the light guide plate (1) is located; a λ/4 wave plate (3), the λ/4 wave plate (3) being arranged between the out-light surface (11) of the light guide plate (1) and the brightness enhancement film (2), an included angle between a slow axis of the λ/4 wave plate (3) and a penetration axis of the brightness enhancement film (2)
