The research focused on the comparing properties of free invertase with immobilized invertase. Methods including purified invertase was extracted from saccharomyces cerevisiae by crushing and then precipitating cool 96% ethanol. Purified invertase was immobilized by alginate gel entrapment. The properties of immobilized enzyme were compared with free enzyme such as special activity, optimum temperature and pH, thermal stability for times. In addition, immobilized enzyme was carried out the reuse and the ability of saccharose hydrolyzing versus time of the optimum. Some results are following: optimum concentration of immobilization is 3.5% alginate which special activity = 3.62 UI/mg-Pr, immobilized yield of special activity = 39.14%, protein–enzyme immobilized yield = 64.27%, recycle is 20 times and the thermal stability is 72 hrs with 7% saccharose hydrolyzing.