Under the influence of topography and climate,plateau grassland soil experiences frequent soil moisture fluctuations. To explore the influence of soil moisture fluctuations on CO_2 and N_2O emission from alpine meadows in the Qinghai-Tibet Plateau,we used an undisturbed soil column to simulate soil water content fluctuation from a high (60 cm~3·cm~(-3)) to low value (30 cm~3·cm~(-3)),and to a high (60 cm~3·cm~(-3)) again; this duration of each phase was 38,57,and 46 days. A soil column with constant HYPERLINKjavascript:; humidity level (soil humidity 60 cm~3· cm~(-3)) was considered the control. The results showed that: 1) soil moisture fluctuations significantly increased CO_2 emission. A significant relationship was observed between CO_2 emission and soil temperature; additionally,CO_2 emission correlated positively with soil dissolved organic carbon (DOC) concentration in the first high soil-water content phase. 2) Moisture fluctuations significantly decreased N_2O emission. In the control treatment,there was a strong significant negative correlation between N_2O emission and NH_4~+ -N; however,no close relation between N_2O emission and NH_4~+-N level was observed throughout the moisture fluctuation process.