【Objective】This study was designed to investigate the growth and migration of bacteria and phages under different water and nutrient conditions, as well as the process and mechanism of the interactions between bacteria and phages.【Method】Using the agar plate, the interaction of Pseudomonas aeruginosa PAO1 and Pseudomonas aeruginosa phage PA-27-1 were performed.【Result】The coexistence of bacteria and phages is mainly affected by phase-induced lysis of bacteria, motility of bacteria and the diffusion of phages. Moisture regulated the relative water film thickness and connectivity on the porous surface of plates. It also affected the movement and proliferation of bacteria, the formation process of biofilms, and morphological characteristics of colonies on the porous interface. Additionally, it regulated the interaction mechanism between bacteria and phages by affecting the spread of phages. Different motility patterns and individual sizes between bacteria and phages also led to differences in their proliferation (diffusion) characteristics in micro-pores. Lower water film thickness and patchy distribution promoted the spatial isolation between bacteria and phages and reduced the probability of phage-reduced lysis, which was important for the proliferation of bacteria.【Conclusion】This study reveals the migration of phages and bacteria in micro-habitats like biofilm and provides a theoretical basis and data support for the temporal and spatial distribution of soil phages, as well as the interaction pattern between soil phages and soil bacteria.