<p>With human activities like exploration, geological investigation and tourism, the structure and function of karst cave microbial communities are prone to change. In this study, sediments from seven different spots in the Dushan Tian Cave in Guizhou Province, China were collected. And the structure and potential key metabolic functions of the microbial community were analyzed through metagenomics. The results showed that the structure of the microbial communities was associated with human-impacted environmental factors. Total phosphorus and Sulfide might promote the growth of <i>Gemmatimonadetes_bacterium</i>. However, Sulfide and organic matter might inhibit the growth of Gemmatimonadetes, <i>Gemmatimonadetes_bacterium</i>, Acidobacteria and <i>Candidatus_Rokubacteria</i>. Human activities triggered ecological effects. In terms of the abundance, denitrification genes increased but ammonia oxidation genes decreased in nitrogen metabolism, suggested there was an increasing trend in the potential of denitrification function. The sulfur metabolic potentials mainly involved assimilatory sulfate reduction where sulfates might be accumulated. The potential of carbon metabolism showed a trend towards the decomposition of exogenous carbon. The methane potential had changed. This study revealed the impact of human activities on cave microorganisms and clarified the response mechanism of cave microorganisms under human interference. It provided an important reference for the ecological protection and development and utilization of karst caves.</p>