The invention discloses a side type backlight module and a display device. The side type backlight module comprises a light guide plate and a light source, wherein the light inlet side of the light guide plate is an oblique face, the light source is obliquely arranged, and the light outside side of the light source is opposite to the light inlet side of the light guide plate. In this way, by arranging the light inlet side of the light guide plate into an oblique face, the light source inclines along the oblique face, the light guide plate is designed and formed in a beveling mode based on the principle that the hypotenuse of a right triangle is the longest, so that the light guide plate adopting the oblique face is thinner on the premise that the area of the light inlet side of the light guide plate is unchanged, and then the side type backlight module is made light and thin. Furthermore, by adopting the oblique face for the light inlet side, area is increased, oblique light transmitted by the light source can be effectively shielded, the problem of bright band on the light inlet side of a traditional side type backlight module is solved, and silk screen letterboxing is not needed.