Rabbitfish, Siganus fuscescens 16.6 to 24.3cm in fork length caught off Tokushima Prefecture in the Pacific Ocean were used for these experiments. These fishes were reared by feeding fish only (experiment I) and both fish and seaweed (experiment II) under continuous flowing seawater conditions during November 2015 to February 2016 and the influence of low water temperature in winter on the survival and feeding was examined. The feeding on fishes stopped at 10.6-10.7 and on seaweed stopped at 12.9degC. Siganus fuscescens in experiment I started to die from 11.1degC (January 24) and one in experiment II from 10.4degC (February 11). These results show that low water temperature below 10.6-12.9degC led to exhaustion of Siganus fuscescens. The lower limiting water temperature for survival was estimated to be 10.4-11.1degC and feeding on both fish and seaweed enhanced the tolerance to low water temperature.