The viscera of three species of freshwater fish，grass carp，bream and silver carp，were used as raw material for fish oil extraction in this study. Emphasis was put on the conditions for visceral oil extracting technology. The method of water bath extraction was employed，and extraction efficiency and quality of oil were evaluated. Selecting time，temperature and the amount of alkali added as main parameters in the orthogonal design，the optimum parameters for visceral oil extraction from the freshwater fish were established. Thus，they will be helpful to the pilot-scale production.