1. Experiments were conducted to observe the chilling requirement of some deciduous fruit trees for the breakdown of bud dormancy in Kochi Prefecture. One-year-old potted trees of each species were kept in the controlled temperature chambers of -1_??_0°C and -7°C, respectively, during the certain period of 5 to 40 days up to January 20, 1957. After the treatment, the plants were placed in a warm room of 6_??_11°C for 8 days, and then in a warm glasshouse of 18_??_21°C. On April 20, they were brought to outdoors and the sprouting time, the number of buds sprouted, the period from the first to the last sprouting, and shoot elongation were observed. 2. As the result of the treatment of -1_??_0°C, the following period up to January 20 was the best for the buds to sprout early, regularly and uniformly, and for the shoots to grow well : 25_??_30 days for peaches, 25 days for Japanese pears, 20_??_25 days for grapes, and 5_??_10 days for Japanese persimmons. However, when treated with -7°C, numerous buds of every species especially near the top of thctree were much damaged, so that the percentageof buds sprouted, and the total amount of shoot length were much inferior as compared with when treated with -1_??_0°. Moreover, when the treat-ment of -7°C continued more than 30 days, all ofthe buds of grapes and Japanese persimmons were frozen to death. 3. In Japanese pears, grapes, and Japanesepersimmons, the shoots sprouted from the upperpart of the tree grew more vigorously than thosefrom the lower part, regardless of the treatment. However, in peaches the result was somewhat. different, that is, only when treated with -1_??_0°C, the shoot sprouted from the upper part of the tree, grew well, while when not treated, the shoots from. the lower part grew better. The fact suggests to us that the winter temperature in the coastal region of Kochi Prefecture is too high for the breakdown of the dormancy of peach buds at the upper part of the tree.