The invention discloses an echo cancellation method and device for eliminating acoustic echo in speech communication. The method comprises a step of receiving a sound signal collected by a microphone, a step of detecting a current communication state, and attenuating a remote speech signal when a detection result is a double-talk state, a step of estimating a linear echo signal according to the attenuated signal, eliminating the linear echo signal from the received sound signal collected by the microphone so as to obtain a residual signal, and transmitting the residual signal to a network. In the scheme provided by the invention, when the current double-talk state is detected, firstly the remote speech signal is attenuated, then the echo signal is estimated according to the attenuated signal, the echo signal in the sound signal collected by the microphone is eliminated, in this way, the echo signal in the double-talk state can be reduced greatly, and the communication effect is improved.