An exemplary method for making backlight module frame includes: providing a plurality of metallic sheets cooperatively defining a frame shape, and a positioning device comprising a worktable and a plurality of positioning portions defined at corners of the worktable, wherein each metallic sheet comprises a first positioning protrusion corresponding to the positioning portions, positioning the metallic sheets on the worktable of the positioning device with the first positioning protrusions of the metallic sheets engaging with the positioning portions of the positioning device, welding the metallic sheets together to form a semi-manufactured frame, and pressing the semi-manufactured frame to form a backlight module frame.