Potato peel waste (PPW), a zero-value byproduct generated from potato processing, is a promising fermentation substrate due to its large quantity of starch, non-starch polysaccharide, lignin, protein, and lipid. Rhizopus oryzae is a filamentous fungus that is mainly known as a lactic acid producer and can ferment various agro-wastes. This study aimed to use R. oryzae for the fermentation of PPW. A series of batch fermentations were conducted to investigate the effects of different PPW loading rates (2 – 8%) and particle sizes (0 – 4mm). Under an initial PPW loading rate of 8% and particle size of 1 – 2mm, the maximum ethanol (23.9 mL/L) and lactic acid (2.60 mL/L) concentrations, the highest ethanol (11.93 mL/L•day) and lactic acid (1.56 mL/L•day) maximum production rates were obtained. Under these conditions, the yield of ethanol and lactic acid were 298 mL/mgPPW and 33 mL/mgPPW, respectively. R. oryzae was shown to utilize PPW as a substrate to produce value-added bioproducts such as ethanol (major product) and lactic acid.