Co/Fe layered double hydroxides (Co/Fe-LDHs) was prepared by coprecipitation method, and calcined Co/Fe layered double hydroxides（Co/Fe-LDO） was obtained after calcination. The structure and properties of Co/Fe-LDHs and Co/Fe-LDO were characterized by XRD, SEM, BET and XPS. The in-fluencing factors and mechanism of phenol degradation by Co/Fe-LDHs or Co/Fe-LDO activated persul-fate were studied．The results show that the specific surface area is increased from 41.2 to 56.8 m2/g and pore volume is increased from 0.2 to 0.3 cm3/g by calcined method, so the activation ability of persulfate is significantly improved. As reaction time was 30.0 min, reaction temperature was 25.0 °C, dosage of Per-sulfatewas 0.2 g/L, dosage of Co/Fe-LDO was 0.2 g/L, pH was 6.0 and initial phenol concentration was 100.0 mg/L, the phenol degradation rate reached 90.1%. The phenol degradation of persulfate activation by Co/Fe-LDO mainly due to SO4−• and •OH.