Abstract: The decomposition of elastic wavefields is key to anisotropic elastic reverse-time migration(ERTM).Because the P- and S-waves in anisotropic materials are not polarized parallel and perpendicular to the wave vectors, respectively, the wavefield decoupling method based on Helmholtz decomposition and that based on isotropy in the time-space domain are not suitable for anisotropic media.This unsuitability is because their use results in crosstalk of P- and S-waves after decoupling, and ultimately affects the imaging quality.The anisotropic wavefield decoupling methods in the wavenumber domain are computationally expensive owing to the Fourier transform at each period.In this study, we propose a time-space domain wavefield decomposition method, which first decomposes the elastic parameter in transversely isotropic(VTI) media into the P- and S-wave constants, and then substitutes them into the elastic wave equation to obtain the decomposed P- and S-elastic equations.According to this process, we can obtain the vector P- and S-waves.This method is simple and does not require amplitude or phase correction, which will promote the industrialization of elastic reverse-time migration in VTI media.A simple model was used to test the separation effect of the elastic wavefield, which revealed that little crosstalk still exists after this process.Moreover, a single trace was used to analyze the crosstalk of the decomposed vector wavefield.A standard model was used to test the elastic reverse-time migration.The imaging results show that the interface information is consistent, has a high signal-to-noise ratio, and can clearly describe complex structures, such as faults and folds.Additionally, no imaging artifacts or depth inconsistencies are present.The model test demonstrates the adaptability of the proposed method.