Bryophyte communities at altitudes of 800 m to 2400 m on both rocks and soil were investigated in Dabashan National Nature Reserve, Chongqing. Niche breadth and niche overlap of dominant bryophytes on the two substrates were calculated and analyzed, using vegetation type as the resource. Variance ratios (VR), χ² tests, and association coefficients (AC) were used to analyze interspecific associations. The results showed that the highest importance values of dominant bryophytes on both rocks and soil occurred in deciduous broad-leaved forest. Niche breadth values of the 15 most-dominant bryophytes on rocks ranged from 0.574 to 1.783. Among these species, Thuidium cymbifolium had the highest niche breadth value. On the other hand, niche breadth values of the 10 most-dominant bryophytes on soil ranged from 0 to 1.361; that of Entodon concinnus was the highest. Niche overlap between dominant species on rocks and soil varied from 0.048 to 0.939 and from 0 to 0.998, respectively. The VR values were both less than 1 and the W values were outside the confidence intervals, which indicated that there were significantly negative correlations between dominant species on rocks and on soil and that the bryophyte communities were in the primary stage of succession. Interspecific associations of 37 bryophyte species pairs on rocks and 20 species pairs on soil reached significant levels. Niche breadths of the same species, and niche overlap and AC of the same species pairs on the two different substrates were different.