The invention discloses a desorption and regeneration method for an organic matter adsorbent. The method is characterized in that an organic matter adsorbent desorption and regeneration device of a microwave generator is arranged in a desorption tower; the to-be-desorbed adsorbent with organic matters is put in the desorption tower; steam is aerated from the top of the desorption tower; the microwave generator is started, wherein the microwave power is 500-10000W; desorption is carried out for 2-30 minutes; the desorbed organic matters and steam flow out from a steam outlet at the bottom of the desorption tower and enter a condenser for condensation; then the steam is cut off, nitrogen is aerated from the top of the desorption tower, and the nitrogen flows out from the bottom, wherein the microwave power is 200-2000W; drying treatment is carried out for 2-20 minutes; the microwave generator is turned off, and the nitrogen is cut off; the desorbed adsorbent is obtained. According to the method, the desorption rate is improved by a large margin by combining steam and the microwave technology, and less desorption residue is left.