The present invention provides a method for constructing a universal LED bulb, a snap ring structured LED bulb and a lamp. The constructing method comprises: supporting an optical engine core member of the LED bulb in the lens snap ring (8) using a lens snap ring (8) as a supporting main body, using an inner snap ring (81) provided on the inner side of a light distribution optical lens (7) in the optical engine core member as an auxiliary supporting structure, and further using the inner snap ring (81) as an installation base of an optical engine module (4) and a heat conductive bracket (3) or an installation base of an LED bulb radiator (103); the optical engine core member of the LED bulb is composed of the heat conductive bracket (3), the optical engine module (4), the inner snap ring (81) and the light distribution optical lens (7).