The present invention relates to a microorganism regeneration method for treating granular active carbon achieving the saturated nonyl phenol adsorption state, and belongs to the field of environmental engineering. The method comprises: 1, adding pre-treated granular active carbon to an aqueous solution with a nonyl phenol concentration of 4 mg/L, and adsorbing for 12 h to make the active carbon achieve adsorption saturation, wherein the active carbon mass concentration is 0.1 g/L; 2, filtering out the active carbon achieving the adsorption saturation in the step 1, weighing 0.05 g of the active carbon, adding to a carbon source-absent inorganic culture liquid, adding a microorganism solution with the amount of 10% of the mass of the active carbon and for degrading the nonyl phenol, and regenerating for 24 h, wherein the microorganism belongs to Pseudomonadaceae, the temperature is controlled at about 25 DEG C, and the pH value of the system is 5.0-8.0; 3, filtering out the active carbon mixing liquid in the step 2, and washing the active carbon with di-distilled water; and 4, dewastering and drying the washed active carbon so as to obtain the regenerated active carbon. The method of the present invention has characteristics of low cost, no pollution, simple operation, and good active carbon regeneration effect achieving, and is suitable for degradation of low-content and large-harm organic matters in water.