A method of performing a diffused light color temperature switching control for an LED lamp includes using at least a first LED lighting load emitting a first color temperature light and at least a second LED lighting load emitting a second color temperature light, using a light diffuser covering the first LED lighting load and the second LED lighting load to create a diffused light with a diffused light color temperature, using a power allocation circuitry working with a power allocation algorithm to manage different electric powers respectively delivered to at least the first LED lighting load and at least the second LED lighting load while keeping a total electric power unchanged to generate diffused lights with different diffused light color temperatures.