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The feedback effect of land surface radiation budget and energy distribution on land-atmosphere system is one of the most important physical processes in climate models. Studying the effects of disturbance of cloud and precipitation on radiation budget and energy distribution is a crucial link to increase the parameterization effect of evaluating land surface radiation budget and energy balance in numerical models. Based on the data observed at the Semi-Arid Climate and Environment Observatory of Lanzhou University in 2008, the weakening influences of disturbance of cloud and precipitation on components in radiation budget and on land surface energy balance are studied. The annual average results showed that cloudy situation could be thought of as climatic background of annual average; weakening influences of cloud and precipitation on short-wave radiation are the strongest, and atmospheric long-wave radiation increases while surface long-wave radiation decreases with cloud amount increasing; the influences of cloud and precipitation on the ratio of net radiation to global radiation is small. The seasonal average results show that daily integral value of short-wave radiation decreases with cloud amount increasing both in growing season and in non-growing season, and weakening influences of cloud and precipitation on short-wave radiation in growing season are obviously stronger than in non-growing season. In growing season, there is no substantial difference among surface long-wave radiations on clear days, partly cloudy days and cloudy days, and atmospheric and surface long-wave radiation decrease apparently on overcast days. In non-growing season, the influences of cloud and precipitation on surface long-wave radiation are smaller, and its daily integral value changes a little, and atmospheric long-wave radiation increases with cloud amount increasing. The surface albedo has obvious diurnal and seasonal variation characteristics and it is higher in winter than in autumn; the diurnal variation curves of albedo present unsymmetrical "V" shapes. In growing season, sensible heat flux and soil heat flux decreased along with cloud amount increasing; latent heat flux increases with cloud amount increasing on clear, partly cloudy and cloudy days; due to the precipitation on obscure days, latent heat flux decreases greatly because net radiation is seriously weakened. In non-growing season, daily integral value of net radiation is greatest on partly cloudy days, and net radiation on clear days is very close to it on cloudy and overcast days; sensible and latent heat flux decreases with cloud amount increasing, average daily integral value of soil heat flux is negative in non-growing season. In growing season, energy closure degree on cloudy days is best, and imbalance energy accounts for 3.9% of net energy; energy closure degree on overcast days is worst, and imbalance energy accounts for 16.8% of net energy; imbalance energy accounts for 7% of net energy under both clear and partly cloud situations. Due to snow effect in non-growing season, energy closure degree in non-growing season is greater obviously than it in growing season.