A direct-type backlight module, comprising a back plate, an optical assembly, and a middle frame arranged on a front face of the back plate and located at a periphery of the optical assembly, the direct-type backlight module further comprising: a cooling fin and a Mini LED lamp panel arranged between the back plate and the optical assembly; the cooling fin connects to the back plate, the Mini LED lamp panel connects to the cooling fin, and the optical assembly connects to the middle frame while contacting with the Mini LED lamp panel, wherein a Mini LED of the lamp panel is a light emitting diode, LED, having a chip size of 80-300μm; a plurality of core modules disposed at a back of the back plate, wherein the back plate has a plurality of pillars arranged thereon, and the pillars separate the core modules from the back plate; and wherein a bottom of a back surface of the back plate has a reinforcement beam arranged thereon, the reinforcement beam comprises two cross beams and a plurality of longitudinal beams connecting to the two cross beams, and the cross beams and the longitudinal beams are in contact with the back plate to strengthen strength of the back plate; wherein a top surface of the optical assembly has a plurality of openings, and the middle frame has a plurality of hooks adapting to the openings, wherein each of the openings has an elongated shape; and the middle frame comprises: an upper middle frame, a lower middle frame, a left middle frame, a right middle frame, a rear pressing plate, and a front pressing plate, a top surface of an optical film of the optical assembly is hung on one of the hooks on the upper middle frame through one of the openings, and a bottom edge of the optical film is fixed between the lower middle frame and the rear pressing plate through the rear pressing plate to ensure the optical film sticks closely to the Mini LED lamp panel; wherein a back shell is disposed at the back of the back plate and the core modules are located inside the back shell. a plurality of core modules disposed at a back of the back plate, wherein the back plate has a plurality of pillars arranged thereon, and the pillars separate the core modules from the back plate; and wherein a bottom of a back surface of the back plate has a reinforcement beam arranged thereon, the reinforcement beam comprises two cross beams and a plurality of longitudinal beams connecting to the two cross beams, and the cross beams and the longitudinal beams are in contact with the back plate to strengthen strength of the back plate; wherein a top surface of the optical assembly has a plurality of openings, and the middle frame has a plurality of hooks adapting to the openings, wherein each of the openings has an elongated shape; and the middle frame comprises: an upper middle frame, a lower middle frame, a left middle frame, a right middle frame, a rear pressing plate, and a front pressing plate, a top surface of an optical film of the optical assembly is hung on one of the hooks on the upper middle frame through one of the openings, and a bottom edge of the optical film is fixed between the lower middle frame and the rear pressing plate through the rear pressing plate to ensure the optical film sticks closely to the Mini LED lamp panel; wherein a back shell is disposed at the back of the back plate and the core modules are located inside the back shell.