The invention provides a channel state detecting method and device. The channel state detecting method comprises the steps of obtaining a system observation value within a current detection period; calculating a channel estimation value and a pulse noise estimation value of the current detection period based on the system observation value and prior information; and determining the channel state in the current detection period based on the channel estimation value and the pulse noise estimation value. As the pulse noise is estimated in a wireless electromagnetic environment with random pulse noise, indeterminacy of statistic information in a channel state detecting process is removed efficiently, false-alarm detection caused by pulse energy is reduced to the maximum limit, and the accuracy of channel state detection in the presence of complex electromagnetic pulse noise is improved obviously.