Theacrylamide(AM) and acrylic acid(AA)withstrong waterabsorption andexpansibilitywere used as main monomers,with 2-acrylamide-2methyl propane sulfonic acid(AMPS) and methyl acrylyl ethyl trimethyl ammonium chloride(DMC) as functional monomer, and a core-shell typeP(AM-AA-AMPS-DMC)nano-microsphereswas preparedby inverse emulsion secondary polymerization.Thepolyacrylamidenano-microspheres were characterized by using FTIR,TG,XRD,TEM,laser particle size analyzer,rheological analyzer and stability analyzer.The results show that monomers AM, AA, AMPS and DMChavepolymerized completely, and P(AM-AA-AMPS-DMC)microspheres have good thermal stability, with smooth surface,uniform distribution and core-shell type structure.Thestorage stability of the nano-microspheresemulsionismorethan6 months.Theheat resistance and salt resistance of the nano-microspheres were characterized by testing expansion rateof nano-microspheresinmineralized waterwithsalinityand at differenttemperature. The experimental results show thatthe average particle size of nano-microsphereswas expanded from 260nm to1168nm as the prolongating of ageing time. Theexpansion rateincreasedwith temperature increasing andtheexpansion rateof P(AM-AA-AMPS-DMC)nano-microspheresat60℃reached to4.1times.With the increase of shear rate,the P(AM-AA-AMPS-DMC)emulsion shows the shear thinning behavior and it has a particularviscoelasticity.