In 1987 and 1988, fruit growth and variations of endogenous growth hormones in Chinese gooseberry (Actinidia chinensis Planch. cv. Monty) were examined to demonstrate the fruit growth cycle and its relation to endogenous hormones. The results obtained were as follows: 1. Fruit growth measured by volume, fresh weight and dry weight followed a double sigmoid curve, and was divided into three stages; i.e., stage Ⅰ (anthsis to 8 weeks after anthesis) characterized by rapid growth of fruit and seed, stage II (8-14 weeks after anthesis) characterized by slow growth of fruit and rapid growth of embryo, and stage I characterized by second growth and maturing of fruit. 2. The activities of 2 auxin-like substances A Ⅰ (Rf 0.3-0.5) and A Ⅱ(Rf 0.7-0.9), 2 gibberellin-like substances GA Ⅰ (Rf 0.2) and GA Ⅱ(Rf 0.5-0.6), Cytokinin, and ABA-like substances (probably ABA) were detected in developing fruit. 3. In stage Ⅰ, very high activities of GA Ⅰ and GA Ⅱ, and the highest activities of cytokinin and ABA were detected in fruit 1 week after anthesis, but after this time their activities decreased rapidly. The highest activities of A Ⅰ, A Ⅱ, and GA Ⅰ were detected in fruits 2, 4 and 5 weeks after anthesis respectively, but after these times their activities decreased rapidly. It is inferred from these results that in fruit just after anthesis its growth may be regulated by the combinations of GA Ⅰ, GA Ⅱ and A Ⅰ with functions to prevent abscission, Cytokinin with a function to promote cell division and ABA with a function to promote abscission, and that in fruit after this time its growth may be promoted by A Ⅰ, A Ⅱ and GA Ⅰ with functions to expand cell wall and activate cell metabolizm. 4. Since all hormones, except auxins detected just before stage Ⅰ, exhibited very low activities throughout stage Ⅱ, it is comfirmed also from these hormone levels that the intervening slow growth phase (stage Ⅱ) exists in the process of Chinesis gooseberry fruit growth. In addition, since remarkable growth of embryo and increase in dry weight of seed and fruit occured also in stage Ⅱ, another internal factors resulted in the intervenig slow growth phase are considered to be competition of nutrient absorption between fruit and other parts of the tree and, espacially, between seed and other parts of the fruit. 5. Relatively high activeties of A Ⅰ and A Ⅱ were detected just before and at the begining of Stage Ⅲ, whereas after this time they decreaced rapidly. Conversely, ABA level was low at the beginning of stage Ⅲ, Whereas it increased as the fruit becomes mature. No hoemones other than A Ⅰ, A Ⅱ and ABA were conspicuous in stage Ⅲ. It is inferred from these results that second growth of fruit in stage Ⅲ is mainly regulated by A Ⅰ and A Ⅱ with functions to expand cell wall, and that after the cessation of second growth ABA activates the metabolism related to maturation of fruit and, subsequently, promotes ripening of fruit. Another internal factor resulted in second growth of fruit is considered to be increase in intake of dry matter in the pericarp, since dry weight of fruit remarkably increase up to 19 weeks after anthesis in stage Ⅲ. 6. In stage Ⅰ, auxin levels were higher in the innerpericarp than the outerpericarp, whereas ABA level was higher in the outerpericarp than the innerpericarp. However, no differences in ABA and gibberellin levels were detected between the inner and outerpericarp during stage I and throughout the three stages respectively. Some of these results indicate that, so far as first growth is concerned, fruit growth is dependent on hormones produced by the developing seeds and the others indicate that fruit growth is dependent on hormones synthesized by the fruit flesh itself. Relationships between fruit growth cycle and endogenous hormones have been resolved to such an extent as shown in the present study. However, final clarification of growth cycle is difficult to obtain from these results until we have a picture of the mechanism of action of each class of hormone synthesized in each organ of the fruit tissue and each that synthesized in pollen tube within a pistil.