Abstract: It is difficult to describe the rheological behavior and flow process of paste due to its diverse composition and changeable transport environment. In this study, the micro and mecro-structure analysis and the quantitative study of low-field nuclear magnetic resonance (LF-NMR) were used to scientifically and accurately describe the existing form of cross-scale particle groups and the water occurrence state in paste. In addition, the flow pattern evolution law of paste particles under the disturbance of pump pressure was analyzed based on the finite element and discrete element coupling numerical analysis method. It was found that the adsorption water, interstitial water and weak free water in paste had dynamic connectivity and transformation behavior, and the water in paste mainly existed in the form of adsorption. According to the analysis of LF-NMR, the relaxation intensity and the peak area of the adsorbed water were nonlinearly enhanced, showing a significant positive correlation with the flow performance of the paste. The liquid network structure and the floc network structure reflected the activity of water flowing channel and the strength of force chain structure respectively, and together constituted a double-supported skeleton structure that determined the stability and fluidity of the paste. The Fluent-EDEM coupling simulation was applied to analyze the particles movement behavior in pulse pumping environment. The velocity difference aggravated the impact disturbance of particles with high and low flow velocities, enhanced the force chain contact effect, and effectively improved the flow uniformity and the overall stability of particles motion.