Leaf functional traits play an important role in the response of plants to environmental change. How leaf traits respond to precipitation pattern and short term extreme drought is still not very clear in Inner Mongolia typical steppe under climate change. By using manipulative experiment in the field, the leaf traits of dominant species Leymus chinensis and community leaf traits were studied under precipitation pattern (323 m and 266 mm) and short term extreme drought (precipitation reduced by 66% from May to September; drought for 60 days from June to July) in Inner Mongolia typical steppe. The results showed that precipitation had significant effects on leaf traits L. chinensis and community leaf traits (P<0.05), and short term extreme drought significantly affected leaf area of L. chinensis and community weighted means of leaf area. Specifically, leaf area and leaf dry matter content of L.chinensis and community weighted means of leaf area and leaf dry matter content decreased from high precipitation site to low precipitation site, while leaf nitrogen content increased. The interaction of precipitation pattern and short term extreme drought significantly affected community weighted means of leaf area and leaf nitrogen content (P<0.05). Short term extreme drought significant decreased community weighted means of leaf area in 323 mm, and drought for 60 days significantly increased community weighted means of leaf nitrogen content in 266 mm. Precipitation pattern and short term extreme drought interactively affected leaf area and specific leaf area of L.chinensis (P<0.01). Short term extreme drought significantly decreased leaf area of L.chinensis in 323 mm, and drought for 60 days increased specific leaf area in 266 mm. Leaf area, leaf dry matter content and leaf nitrogen content of L.chinensis can well explain community leaf traits under control and short term extreme drought treatments. Dominant species can alter the key leaf traits to acclimate to precipitation pattern, while they change leaf area to adapt to short term extreme drought in typical steppe.