Abstract: With the increasing application of simultaneous source seismic data acquisition method in seismic oil and gas exploration, many scholars have studied the key technology of simultaneous source seismic data blending interference noise separation. So far, research on methods with higher fidelity is still needed. This article is based on the following assumptions: Normal Moveout Correction(NMO) in simultaneous source seismic data can enhance the linear distribution degree of reflection(especially in Common Middle Point(CMP) gather), and expand the distribution difference of reflection and blending interference noise; single domain separation of blending interference noise only aims at a certain distribution characteristic difference of blending interference noise and reflection; multi-t-x domain combined separation can comprehensively utilize the distribution difference of blending interference noise and reflection in each t-x domain, and its separation effect is better. We first use NMO for simultaneous source seismic data CMP gather to enhance the linearity of the reflection, and expand the dispersion of randomly distributed blending interference noise. Secondly, we use median filtering to separate most of the blending interference noise. Finally, based on the residual blending interference noise distribution in other t-x domains(such as Common Shot Gather(CSG), Common Receiver Gather(CRG) and Common Offset Gather(COG) etc.), the random noise attenuation is used for further separation, and the amplitude-preserving method is used in the whole separation process. The multi-t-x domain combination separation method is verified by theoretical data, and compared with the single domain separation method, it can effectively separate blending interference noise from simultaneous source seismic data with high fidelity, and suppress other noises and shear waves to a certain extent. The actual data results show that the method has better suppression effect and better seismic profile results.