The invention relates to an electroencephalogram data type annotation method and system in a conscious state, wherein the method comprises the following steps that after a user starts a sleeping process, an electroencephalogram sample of the user is collected; the electroencephalogram sample is subjected to wavelet decomposition; the signal rebuilding is performed according to the wavelet coefficient of the set low frequency band to obtain an electroencephalogram; the sample entropy of the electroencephalogram is calculated, and is compared with a pre-calculated sample entropy threshold vale; if the sample entropy is greater than the sample entropy threshold value, the signal type of the electroencephalogram sample is annotated into the conscious state. By using the technical scheme, the method and the system have the advantages that the electroencephalogram is prevented from being interfered; the conscious state of the electroencephalogram is accurately detected; in addition, the effective data type annotation is performed, so that the recognition accuracy of a personnel classifier trained by using the annotated electroencephalogram sample is higher; the reliability of the detection result of the personnel sleeping stage in the later period is also improved.