To elucidate fertilizer responsiveness of rice cultivars as Akenohoshi and Nishihomare which were bred to obtain many grains in number per unit area, the comparisons of characteristics of dry matter production and accumulated carbohydrate at heading between these and 9 cultivars including IR24 and Suweon 258, which had high fertilizer responsiveness, were carried out on three nitrogen levels (8, 14, 22 kg/10a). The results were as follows; 1) The high yield of Suweon 258 and IR24 on heavy fertilizer was attributed to both the large total dry weight at harvesting and harvest index. The low yield of Nishihomare and Akenohoshi was attributed to low harvest index and small total dry weight, respectively. 2) The dry matter production of Suweon 258 and IR24 after heading on heavy fertilizer was higher than on standard fertilizer, but that of Akenohoshi and Nishihomare was opposit. 3) Accumulated carbohydrate amount of Suweon 258, IR24, and Nishihomare at heading was more than that of Akenohoshi. 4) The low percentage of ripened grains of Akenohoshi was attributed to small amount of accumulated carbohydrate per sink size.