The invention discloses a spectrum sensing method and device based on Hilbert-Huang transform, wherein the method comprises the steps of: obtaining a signal to be detected, and performing EMD decomposition of the signal to be detected, so that n corresponding IMF components are obtained, wherein the signal to be detected is a wireless spectrum signal; obtaining the Hilbert spectrum of each IMF component, and superposing the Hilbert spectrums respectively corresponding to the first IMF component to the ith IMF component, so that the total Hilbert spectrum is obtained, wherein i is less than n; accumulating the total Hilbert spectrum in terms of time to obtain a marginal spectrum; and, judging whether the marginal spectrum is greater than or equal to the pre-set judgement threshold value or not, if so, determining that a main user signal exits in the signal to be detected, and if not, determining that the main user signal does not exist in the signal to be detected. By means of the technical scheme provided by the invention, the local feature of the wireless spectrum signal can be reflected accurately; and thus, the spectrum sensing accuracy rate can be greatly improved.