Abstract: A light source module and a method for manufacturing the same, and a backlight module and a display device using the same are provided. The method includes the following steps. A reference light source module is provided. The reference light source module comprises a substrate and plural light-emitting units arranged on the substrate. Then, plural optical trends between every two adjacent light-emitting units are obtained. Then, plural optical ratios between every two adjacent light-emitting units are calculated, in which each of the optical ratios is a ratio of each of the optical trends to a total reference optical trend of the reference light source module. Then, plural target distances are calculated according to the optical ratios and plural initial distances between every two adjacent light-emitting units are adjusted according to the target distances, thereby forming a target light source module.