Abstract: Taking advantage of the metabolic transformation on a selenium(Se)-enriched wheat bran medium by Pleurotus geesteranus,the nutritional value of the resultant dietary fiber powder could be substantially improved.The average content of biological organic Se content in the wheat bran powder reached 1.63 mg/kg with an added 3 μg·g-1 of sodium selenite that is within the safe threshold of Se nutrition metabolization.The amount was more than 56 times of the Se content in wheat bran,indicating an average Se conversion efficiency of approximately 86%.Aside from Se,the dietary fiber,total protein,total soluble sugars and proteins in the treatment powder did not differ significantly from the control.The result suggested that the cultivation of P.geesteranus on a wheat bran based medium enriched with Se could enhance the inorganic Se transformation improving the bioavailability of the mineral,and thus,the nutritional value of the wheat bran/mushroom powder.