A total of 292 field experiments were laid out and conducted in different regions of Sichuan Province during the period of 2005-2009 to study effect of nitrogen (N) fertilization on rice relative to region, and further to specify features of the crop absorbing N and to lay down scientific basis for recommendation of N fertilization for rice. Results show that N application significantly increased rice yield by 22.4% in the Chengdu Plain (CP), by 33.7% in the hilly region of Central Sichuan (HCS), by 38.9% in the mountainous areas around the Sichuan basin (MAS) and by 33.1% in the mountainous area of Southwest Sichuan (MSWS), which shows that yield response of rice to N application varied with the region due to sharp differences between the regions in landform, climate and soil fertility, and hence in N absorption and utilization rate of the crop. N application increased N absorption per 100 kg grain by 0.19 kg. When N absorption of the crop reached 281.8 kg hm^-2, yield of the crop could be as high as 10.0 t hm^-2 in MSWS. In terms of average N recovery rate (REN) CP was the lowest (32.2%) and MAS the highest (36.7%). Agronomic efficiencies (AEN) of the regions varied from 11.5 to 14.4 kg kg^-1. Difference in landform between the regions is the major factor explaining the difference between the crops in different regions in N recovery rate. The findings of the study suggest that rational recommendation of N fertilization rate in light of landform of a region should be an effective way to improve N use efficiency of rice cultivation in Sichuan Province.