Abstract: An investigation was conducted on the bryophyte communities from stream and waste solid subareas of the upper stream of Cat Stone Reservoir, a high-arsenic coal area in Xingren County, Guizhou Province. It was found that there were 6 species of 6 genera in 5 families in the bryophyte communities, and the dominant species presented more apparent features. Hyophila rosea of Pottiaceae and Polytrichum commune of Polytrichaceae were the dominant species in the stream and waste solid subareas, respectively. Due to the contamination of the acid mine drainage, the electric conductivity and acidity were high in the growth matrix of the bryophyte, which made the species of bryophytes in the study area largely different from those found in other areas. The arsenic (As) concentration ranged from 2.65 to 282.70 mg·kg^-1 across different bryophyte species, with an average concentration of 79.28 mg·kg^-1. The distribution of As in different parts of the dominant species Hyophila rosea showed that soil matrix was one of the sources of As in the Hyophila rosea.