The invention discloses an efficient spectrum sensing method based on a support vector machine. The efficient spectrum sensing method comprises the following steps: S1, inputting a to-be-sensed receiving signal; S2, preprocessing the to-be-perceived received signal through PCA (principal component analysis), and decomposing a covariance matrix of the to-be-perceived received signal by adopting Dullet decomposition to obtain feature statistics; S3, obtaining a label of a to-be-perceived received signal through an energy detection algorithm, and forming a sample training set by the obtained label and the obtained feature statistics; S4, inputting the formed sample training set into a support vector machine SVM classifier for training to obtain a spectrum classifier; and S5, inputting the collected data into a spectrum classifier for processing to obtain a classification result. According to the method, the high spectrum recognition rate can still be achieved under the condition of the low signal-to-noise ratio, meanwhile, due to introduction of the non-progressive threshold, the progressive threshold changes along with the environment, and spectrum sensing is more accurate.