Environmental factors are the main factors affecting the intraspecific variation of plants, and leaves are the organs most susceptible to the environment. In order to explore whether the leaf epidermal micromorphology has longitude variation and its influencing factors, we investigated the stomatal density, stomatal index, epidermal hair density, stomatal apparatus length and stomatal apparatus width of 8 populations of Caragana intermedia in the Inner Mongolia Plateau. The regression analysis is used to explore its degree of variation and impact factors. The results showed that: (1) the epidermis of the Caragana intermedia is covered by single cell nonglandular hair, the stratum corneum is rough, and the stomata are subsided which were the characteristics of drought resistance. The mean of stomatal density, stomatal index, epidermal hair density, stomatal apparatus length and stomatal apparatus width in the upper epidermis of C. intermedia were 302.81 pieces/mm², 9.94, 204.81 pieces/mm², 11.78 μm, 5.95 μm, and the lower surface of the leaves were 272.83 pieces/mm², 10.43, 187.45 pieces/mm², 12.49 μm and 6.18 μm, respectively. (2) The stomatal density and stomatal index increased with the increase of longitude, while the leaf epidermal hair density decreased with the increase of longitude. (3) The plasticity index of the epidermis is: epidermal hair > stomatal density > stomatal index > stomatal apparatus width > stomatal apparatus length. The leaf epidermis of C. intermedia responds to the changes of the environment mainly by adjusting the epidermal hair density and stomatal density. Sunlight hours, effective accumulated temperature, relative humidity, soil total carbon, total phosphorus and total nitrogen contents significantly affected the micromorphological characteristics of leaf epidermis.