A method for manufacturing an LED module includes following steps: providing a SMT (Surface Mount Technology) apparatus having a CCD (Charge-Coupled Device) image sensor and a nozzle, and providing a PCB and fixing the PCB in the SMT apparatus; providing a plurality of LEDs and mounting the LEDs on the PCB by the SMT apparatus; providing a plurality of lenses each having a plurality of patterned portions formed on an outer face of the lens, and the CCD image sensor imaging the lens and identifying the patterned portions, and then the SMT apparatus obtaining a location of the lens relative to the LED; positioning the lens on the PCB to cover the LED by the SMT apparatus; and fixing the lens on the PCB.