A method for producing alpha-glucosidase inhibitors utilizing Paenibacillus sp., wherein utilizing a Paenibacillus sp. strain which is deposited at Deutsche Sammlung von Mikroorganismen and Zellkulturen GmbH (DSMZ) and numbered No. DSM 32521 to produce the alpha-glucosidase inhibitors, the Paenibacillus sp. Strain is cultivated in a commercial culture medium or a shrimp/crab residue-contained culture medium, and the alpha-glucosidase inhibitors is separated from a fermented supernatant. The alpha-glucosidase inhibitors have strong inhibitory activity.