Microwave assisted hydroxylamine technology was used to achieve rapid and efficient degradation of perfluorooctanoic acid (PFOA). The degradation efficiency of PFOA (50 mg/L) reached 82.22% after 6 min of reaction when the microwave power, hydroxylamine concentration, reaction temperature and pH were 1200 W, 1.0 mM, 200°C and 3.92, respectively. The reaction system was uniformly heated by microwave through the reactor wall, and the hydroxylamine in the reaction system selectively absorbed microwave energy under microwave conditions, resulting in “hot pot” effect, which promoted the generation of free radicals and improved the degradation efficiency. The free radical quenching experiments showed that superoxide radical (O₂^.–) was the main active group for hydroxylamine to degrade PFOA. The O₂^.– first attacked the carboxyl functional group (-COOH) in PFOA, resulting in the fracture of C―O bond and loss of the hydroxyl group (-OH). After losing -OH, the remainder was unstable and continued to fracture and lose CF₂ step by step, and was finally degraded into F^– and CO₂. Therefore, the PFOA degradation by microwave assisted hydroxylamine reduction provides a reference and theoretical basis for the treatment of emerging persistent organic pollutants.