The invention relates to a light source device and a backlight module. The backlight module comprises a frame, a light guide plate and the light source device. The light source device comprises a base plate, a plurality of light-emitting components and positioning components, wherein the plurality of light-emitting components are positioned on the base plate and emit light rays toward the light guide plate; the positioning components are positioned on the base plate and the side edges of the plurality of light-emitting components and comprise slots and butting parts, wherein the slots are connected with electronic components, and the butting parts elastically butt against the light guide plate so as to position the light guide plate. The side edges of the light-emitting components are provided with the positioning components, and the positioning components can elastically butt against the light guide plate to absorb the swelling amount of the heated light guide plate so as to achieve the purpose of positioning the light guide plate, can also be used as connectors connecting the electronic components, and are used for positioning the light guide plate without blow holes and tongue piece, thus effectively solving the problem generated by the hole breaking of the frame in the traditional structure.