Abstract: The properties and mechanism of high-strength interpenetrating polymer network hydrogel, which was synthesized by 2-acrylamide-2-methylpropanesulfonic acid and acrylamide, were studied according to their mechanical and swelling experiments under different monomer concentrations and ionic strength. Results show that the strength of PAMPSPAAm interpenetrating polymer network hydrogel increases with the increasing of AAm concentration (0.5-4 mol/L)，while the AMPS concentration has a optimal value (1 mol/L) and the highest compressive strength of the interpenetrating polymer network hydrogel is up to 6.46 MPa with 1 mol/L AMPS and 4 mol/L AAm. The compressive strength of PAMPS-PAAm hydrogel increases by 29% when increasing the ionic strength of the water in hydrogels to 0.25 mol/kg compared to deionized water.