Global warming has brought great impacts on the ecological system including extending plants growth period, increasing biomass, increasing photosynthetic rate of the plants with lower optimum temperature without changing stomatal conductance, decreasing the content of sodium, potassium and phosphorus in the leaves. With the temperature increasing, the biomass variations of different types of grassland were inconsistent. Kobresia humilis in alpine meadow would be substitute by other grass and Eymus chinensis would be substitute by Stipa grandis. The insects and rodents were mainly studied with warming which showed that insects increased generations and had a tendency to spread to the high altitude and high latitudes and the rodent increased population density without changing of sex ratio and population age structure. Warming enhanced soil respiration, the activities of soil enzyme and the content of soil bacteria. The present paper summarized the response of each component in grassland ecological system which need further study the influence the grassland ecosystem and biosphere.