The invention provides a method for an esterification reaction of konjac glucomannan. The method adopts a mechanical chemical method and comprises the following steps of: 1, drying the konjac glucomannan until the water content of the konjac glucomannan is less than 4 percent and adding an esterification modifier in an amount of 0.5 to 5 percent based on the total mass of the konjac glucomannan; 2, preparing a grinding medium according to the volume filling rate of 50 to 90 percent of a grinding tank of a vibrating mill; 3, uniformly mixing the konjac glucomannan and the grinding medium, adding the mixture into the grinding tank of the vibrating mill, sealing the grinding tank and starting the vibrating mill to grind for 20 to 60 minutes; and 4, separating the grinding medium from a sample by screening so as to obtain the konjac glucomannan prepared by the esterification reaction. The method for the esterification reaction of the konjac glucomannan provided by the invention adopts the mechanical chemical method and has the advantages of simple and convenient operation, low cost, no pollution and capability of possibly meeting the requirement of industrialized production on different application performance of the konjac glucomannan.