The invention relates to a method for two-channel non-parametric energy spectrum sensing in cognitive radio. The method includes: step one, enabling each cognitive user to receive signals from two channels namely a to-be-tested channel and a blank channel, wherein the blank channel can be a protective frequency band or a certain sub-band reserved in a system; step two, establishing a judgment statistic quantity according to the signals received from the two channels; step three, establishing a judgment threshold according to a given false alarm probability; step four, comparing the judgment statistic quantity with the judgment threshold, if the judgment statistic quantity is larger than the judgment threshold, judging existence of authorized user signals appear, and otherwise, judging absence of the authorized user signals. By the method for two-channel non-parametric energy spectrum sensing in cognitive radio, the problem of how to use the energy detection technique and completely use searched signals to carry out high-accuracy judgment under the condition of noise uncertainty is solved.