A method for producing glucosamine with microorganism comprises of fermenting with a microorganism selected from the group consisting of Monascus pilosus and Aspergillus sp. in a novel low-cost medium, thereby enable it to produce glucosamine; wherein said medium is consisted of commercial Taiwan sugar, soy beam, rice bran and the like; wherein suitable condition for the fermentation is: 150˜300 rpm, pH 4˜pH 8, and 24° C.˜37° C.; wherein, after fermentation culturing, the fermentation liquor is filtered with suction to recover said microorganism biomass, said microorganism biomass is then subjected to steps of cell disruption, hydrochloric acid reaction, neutralization reaction and filtration, to obtain glucosamine produced by the microorganism.