In order to study the effect of nitrogen rate on grain yield and dry matter for double cropping super rice in South China, field experiments were conducted with Liangyoupeijiu, Yliangyou 1, Yuxiangyouzhan and Huanghuazhan as materials. The results showed that there was significant difference in effective panicles, grains per spike, spikelets per m2 and grain yield, however, there was no significant difference in grain filling rate and 1000-grain weight. Compared with N1 treatment, the grain yield of early rice and late rice cultivars in N2 treatment were significantly increased by 6.33%~13.39% and 11.53%~25.06% in 2011, respectively, but were no significant difference in 2012. On average, the highest or higher grain yield were attained by Y Liangyou 1 and Yuxiangyouzhan in early rice and late rice, respectively, and compared to late rice, the yield of early rice were increased by 4.58%~33.94%. Furthermore, the effective panicles had the highest contribution to grain yield, then grains per panicle. Compared with N0 , increased nitrogen rate would significantly improve dry matter and crop growth rate, but there was no significant difference between N1 and N2 in 2012. However, the N-use efficiency of N1 was higher than N2 for all cultivars in two years, and there was significant difference in partial factor productivity of applied nitrogen （PEP）. Therefore, in nitrogen rate of 161~176 kg/hm2, the adoption of long and short growth period super rice cultivars as early rice and late rice , respectively, would improve grain yield and N-use efficiency due to increasing grains per panicle or panicle weight and dry matter based on enough effective panicles in South China.