Based on the warming and altered precipitation experiment platform at Haibei research station, this study investigated the responses of soil inorganic nitrogen to warming and altered precipitation in the growing season in alpine meadow. The results show that 1) warming significantly decreases NH_4~+-N by 47.5% (p=0.001) and NO_3~--N by 85.4% (p=0.021); 2) effect of decreased precipitation on soil inorganic nitrogen is unequal to the effect of increased precipitation, increased precipitation significantly increases NH_4~+-N by 74.7% (p=0.046) and NO_3~--N by 154% (p=0.017), while decreases precipitation tends to reduce NH_4~+-N, but has no significant effect on NO_3~--N; 3) NH_4~+-N and NO_3~--N are positively correlated with soil moisture, but has no correlations with soil temperature. Thus, soil moisture induced by warming and altered precipitation, is the main factor affecting inorganic nitrogen availability in the growing season. This study suggests that inorganic nitrogen availability will increase in tandem with increasing soil moisture, under the background of climate change in alpine meadow on the Qinghai-Tibetan Plateau.