To investigate the effect of environmental temperatures on feeding and drinking behaviour in rabbits, an experiment was conducted with Japanese White male rabbits at 20 and 32℃ (R. H. 60%) on a 12 : 12 hr light/dark cycle (12L : 12D). Ingestive behaviour was recorded using automatic pen recorder connected by a transducer to the spring balance which was equipped with feeding or drinking trough on the scale pan of the balance. The results obtained were as follows: 1. The feed intake was 55.2g/kgW^0.75/day at 20℃ and 92.9g/kgW^0.75/day at 32℃. However the ratio of water intake to feed intake at 32℃ bevame higher than that at 20℃ because of the decrease of the feed intake at 32℃. 2. The rabbits showed nyctohemeral feeding and drinking behaviour both at 20 and 32℃ of environmental temperatures, although the drinking behaviour at 32℃ tended to increase in the light period. 3. The rabbits generally showed intensive feeding behaviour during the latter half of the light and the former half of the dark periods both at 20 and 32℃. The drinking frequency at 20℃ tended to increase during the latter half of the light period but at 32℃ it showed no particular tendency. The drinking time and the water intake at 20℃ tended to increase during the latter half of the light and the former half of the dark periods, although at 32℃ they tended to increase only during the latter half of the light period.