The craters of Jingpo Lake World Geopark breed rare primitive underground forests. This study provides important data for improving the origin of bryophyte floristic geography of volcanic ecosystem in China. Based on previous field surveys, specimen collection and species identification, it is known that there are 53 families, 126 genera, and 292 species of bryophytes.The methods of hierarchical cluster analysis and principal component analysis were used for exploring the floristic geographical characteristics of bryophytes. The results show that: (1) The monotypic and oligotypic genera of bryophytes were dominant in the underground forests in the craters of Jingpo Lake World Geopark, with a total of 106 genera (accounting for 84.13% of the total genera) and 152 species (accounting for 52.05% of the total species). (2) There were 11 floristic geographical components, of which the north temperate was the dominate component (49.12%), followed by East Asia (21.55%), and the third was Endemic to China (8.48%). (3) Endemic to China bryophytes in underground forests may spread along the "North line" through mountain ranges. (4) The similarity of bryophytes flora was the highest between underground forests in cratersof Jingpo Lake and volcanic lava platform of Jingpo Lake. Additionally, seven threatened bryophytes were discovered. In short, the main characteristics of the bryophytes flora of underground forests in the craters of Jingpo Lake were ancient origin, complex composition, significant north temperate properties, and had a profound historical origin with the East Asia. It was a refuge for Endemic to China, rare and endangered bryophytes attribute to the superior microhabitat inside the volcanic cones.