In order to provide a theoretical basis for better protection and utilization of the plant resources of Calanthe, we observed the microstructure, invasion pathway and distribution characteristics of mycorrhizal fungi roots of five species of Calanthe by paraffin section method. The results showed that: (1) the roots of five species of Calanthe were composed of the velamina, cortex and stele. The velamina consisted of 3-6 layers of cells, the cortex was composed of 9-13 layers of parenchymal cells, the phloem and xylem are 8-12 bundles, arranged radially, and the pith was located in the center of the stele. (2) The hyphae invades the cortex through passage cells in the exodermis. The cortex is the main colonization area of endomycorrhizal fungi, Most of the hyphae and hyphae were found in several layers of cortical cells near the exodermis. The hyphae is digested near the nucleus and the nucleus is deformed and expanded. According to the research, the five species of Calanthe may have a wide range of mycorrhizal fungal types, which make these five species of Calanthe have strong ecological adaptability.