The invention provides a method for preparing partially hydrolyzed polyacrylamide by means of simultaneous polymerization and hydrolysis of a reversed-phase microemulsion.The method comprises the steps that acrylamide monomers are dissolved in water and mixed to be uniform, and an aqueous phase solution is obtained; 2, cyclohexane, an emulsifying agent and an initiator are added into the aqueous phase solution, the materials are stirred and mixed to be uniform, and a water-in-oil type emulsion is obtained; 3, an alkaline buffer solution is added into the water-in-oil type emulsion, and a stable alkaline water-in-oil type microemulsion is obtained; 4, a reaction is conducted under the stirring condition, and a partially hydrolyzed polyacrylamide colloid is obtained; 5, the colloid is subjected to hot-air drying and smashing, and partially hydrolyzed polyacrylamide is obtained.According to the method for preparing partially hydrolyzed polyacrylamide by means of simultaneous polymerization and hydrolysis of the reversed-phase microemulsion, the hydrolysis degree of polymers can be adjusted in the polymerization reaction process, a post-hydrolysis technology is not needed, partially hydrolyzed polyacrylamide with a high molecular weight can be obtained, the technology is simple and convenient, the hydrolysis efficiency is high, the product is stable in performance, operation is easy, and industrial production is easy to achieve.