The microwave-assisted alkaline degradation of D-glucose with alumina supported potassium hydroxide towards its conversion into lactic acid is reported. An experimental design approach was used to optimize the variables involved in this transformation. The reaction succeeded in yielding 75C-% of lactic acid starting from D-glucose using 1.5 equiv of KOH at 180 degrees C. The optimal conditions were applied to D-fructose, D-mannose and D-sucrose.