To solve the acoustic emission(AE) signal de-noising problem,de-noising approaches based on empirical mode decomposition and wavelet transform were proposed,including IMF-Wavelet method,EMD-Wavelet method and Wavelet-EMD method.The standard noise signals and AE signals by pencil lead break were used to analyze the de-noising performance.The simulation results indicate that for the standard noise signals,Wavelet-EMD method has stable de-noising performance whether in high or low signal to noise ratio(SNR) case.Wavelet threshold method is not suitable for AE signal de-noising,EMD-Wavelet and Wavelet-EMD method have stable de-noising performance for AE signals.