Disclosed are a uniformly emitting linear LED light source assembly and a method thereof. The linear LED light source assembly comprises a first light strip, at least one second light strip and at least one connecting board which are all provided with a plurality of LEDs closely arranged at equal intervals, wherein the equal interval is less than 3.5 mm to realize uniform illumination. The connecting board connects the first light strip and the second light strip. The LED closest to the first light strip on the connecting board and the LED closest to the connecting board on the first light strip are formed at the same pitch as the equal interval. In addition, the LED closest to the second light bar on the connecting board and the LED closest to the connecting board on the second light bar are formed at the same pitch as the equal interval.