On the basis of the 30year ground observational cloud and precipitation data from 77 meteorological stations as well as NCEP reanalysis data， addressed are the distribution and variation of clouds and water resources in clouds in Sichuan.The analysis results indicate that annually， there were 1935 overcast days， 154.0 precipitation days， 147.1 small/moderate precipitation days （0.1 to 25 mm）， with the annual precipitable water being 181.30 kg〖DK〗·m-2， the total cloud cover being 7.2/10， and the lowlevel cloud cover being 4.7/10 over Sichuan. Cloud cover varied obviously with season: the greatest total cloud cover appearing in summer， the secondary in spring， and the least in winter; the greatest lowlevel cloud cover appearing in summer， the secondary in autumn， and the least in winter. Precipitable water varied also with season obviously， being the greatest in summer， secondary in autumn， and least in winter.The spatial distribution of clouds and small/moderate precipitation days differ obviously over the different parts of Sichuan， while the spatial distribution in summer was different obviously with the annual spatial distribution. In the recent 30 years， total cloud cover fluctuated around the average level with a slightly downward tendency over the plateau， while lowlevel cloud cover， small/moderate precipitation days， and precipitation days fluctuated around the average level with a slightly upward tendency.However， in the basin， total cloud cover， lowlevel cloud cover， precipitation days， and small/moderate precipitation days varied with a downward tendency.The precipitable water had an upward tendency in the 30 years.