Abstract: As a clean energy with huge reserves and a widely used industrial raw material, natural gas hydrate has attracted more and more attention from scholars and industry. The formation process of methane hydrate in the reactor containing polyacrylamide-acrylic acid (PAM-AA) salt solution was experimentally studied, and the effect of PAM-AA hydrogel system on the formation of methane hydrate was revealed. The results show that the hydrogel system promotes the formation of methane hydrate at 2 ℃ and 8 MPa; the hydrogel system inhibits the formation of methane hydrate at 2 ℃ and 4.5 MPa; the PAM-AA hydrogel system can disrupt the normal formation of methane hydrate, manifesting as shortening the time for massive formation of methane hydrate (promoting) and hindering mass transfer between gas and liquid (inhibiting); the experimentally generated methane hydrate forms are divided into two types, namely loose and containing a lot of pores or hard and dense, which correspond to the systems that inhibit/promote the formation of methane hydrate, respectively. Exploring the generation process of methane hydrate in the PAM-AA hydrogel system can provide a reference for the generation, prevention, storage, and transportation of methane hydrate in industrial field.