The lower the protein and amylose contents, the better was the eating quality of non-glutinous rice. The protein content (PC) and amylose content (AC) of rice in 15 planting areas of Hokkaido from 1991 to 2006 were analyzed. The average variation range of protein content was 7.2%-8.6% (7.2%-8.2%) in all planting areas (all years), and the average range of amylose content was 18.3%-22.2% (19.8%- 21.2%). The annual variation of protein and amylose content was 1.4 and 2.8 times of that between planting areas, respectively. This was because the range of the yearly variation in the average temperature and growth characteristics like grain yield during rice cultivation season and some growth stages was 1.6-4.4 times larger than that of regional variation. During the 16 years, the earlier the heading date was, the higher the temperature at the freezing injury sensitive stage of sterile rice seedlings, the lower the sterility, the heavier the 1000-kernel-weight; the higher the grain yield, and the lower the PC.Within 40 days after heading, the daily average temperature reached 843 ℃, and the PC were lowest in the quadratic regression equation. Those relationships wasn’t clear in the area where has high wind speed during tillering, low available rate of soil nitrogen and poor initial growth, on the contrary, between PC and 1000-kernel-weight, a positive relationship was found. The regional variation of PC did not correlate with these growth characteristics, but the lower the ratio of peat soil in the paddy field and the lower the wind speed during tillering, the lower was the PC. On the other hand among both years and regions the earlier the heading date, the higher the CTAH, the lower was the AC. Among areas, the shorter distance from the sea, the lower north latitude and the smaller mean diurnal temperature range during 40 days after heading, the lower was the AC.