In order to effectively separate and identify the noise source of excavator cab, this paper adopts the methods of ensemble empirical mode decomposition (EEMD), principal component analysis (PCA), independent component analysis (ICA) and S-transform (ST) to study. Firstly, EEMD is used to decompose the single channel noise signal collected at the driver’s position into multiple intrinsic mode functions (IMF); Secondly, PCA is used to reduce the dimension of IMFs to remove the redundant IMF; Next, ICA processing is performed on the remaining IMFs to obtain independent IC components; Finally, S-transform is used to analyze the time-frequency of IC component, and the source of IC component is identified by prior experience. The results show that the main noise sources are the vibration radiation noise of related parts in the cab, the combustion noise of diesel engine and the fan noise. After identifying the main noise sources, the next step is to study the contribution of these noise sources, which provides a new idea for noise control.