Aspergillus  niger  and  Saccharomyces  carlsbergensis  were grown in submerged fermentation systems with sucrose concentration at 100 g/ liter and varying concentration of molasses  in Basic Mineral Medium ( BMM) for production and characterization of invertase  by Aspergillus  niger  and  Saccharomyces  carlsbergensis. As compare with Aspergillus  niger the  Saccharomyces  carlsbergensis  produce exceptionally large amount of extra cellular invertase in sucrose and varying conc. of molasses. The optimum temperature of  inveratse for Aspergillus  niger  is 40° C and to that of  Saccharomyces  carlsbergensis  is 50 ° C.  The optimum pH of invertase  for Aspergillus  niger  was found to be 4.4 and to that of  for Saccharomyces  carlsbergensis is 4.8 . The activity of this enzyme under these conditions is 600 µg of reducing sugar /1 min/1 ml of enzymes for Aspergillus  niger and to that of  Saccharomyces  carlsbergensis  is 5040µg of reducing sugar/1 min/1 ml of enzyme. For these two i.e  Aspergillus  niger  and  Saccharomyces  carlsbergensis  the specific activity was found to be 2.25 and 20.16 respectively. Immobilization was also done for getting immobilized cells activity. And finally gel electrophoresis is done to get separate protein bands.