For examining the effects of raw soybean preservation on the quality of tofu, seven varieties of raw soybeans were preserved at 15 degrees C followed by analysis of their components, and the quality of tofu prepared from them every other month was evaluated. At 10 months preservation, no significant changes in compositions of monosaccharide and oligosaccharide of preserved soybeans were found for any varieties. However, urease activity, antigenicity and germination rate had decreased to 83.7%, 15.5% and 90.0%, respectively. Examination of the tofu preparations indicated reduction in tofu volume in proportion to the time of preservation. It is thus evident that the properties of soybean changed significantly during preservation, urease activity and antigenicity may be as possible assessment indicators for the quality of tofu prepared from preserved soybeans, though additional research should be conducted for-confirmation of this point.