Abstract: A survey of medicinal plants resource and diversity in Inner Mongolia was conducted for their effective exploitation and protection by used literature review and analysis of clustering method. The result showed that fern, conifers and angiosperm medicinal plants in Inner Mongolia were found to include 1207 species, belonging to 521 genera and 123 families, which account for 1021%, 2381% and 4576% of the respective species, genera and families of medicinal plant resource in all of China. There are 526 species of medicinal plants using as Mongolia medicinal materials, accounting for 4358% of the medicinal plants there. Dominant families are mainly Composiatae, Rosaceae, Ranunculaceae, Labiatae etc; dominant genera are mainly Artemisia, Polygonum, Potentilla, Saussurea, etc. Furthermore, there are 992 species of herbs, occupying 8218%, and whole herbs used as medicinal materials occupy 4341% of the medicinal plants there. Cluster analysis based on Euclidean distance showed that medicinal plants could be divided into two groups: Alashan, Yikezhao, Huhhot, Baotou and Bayannur League composed one group, while Chifeng, Hulunbuir, Ulanqab, Xilingol, Xingan, and Jirem League constituted one group. This study showed that medicinal plant resource in Inner Mongolia was very rich, and Ulanqab was clear boundary of their distribution.