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<strong class="journal-contentHeaderColor">Abstract.</strong> Nitrated aromatic compounds (NACs), a major component of brown carbon (BrC), have a significant role in the atmosphere&rsquo;s ability to absorb light. Despite this, the sources and major influencing variables of the mountain background atmosphere are mostly lacking. The current work is based on a thorough field investigation of NACs from fine particle samples taken in 2014 and 2015 at the peak of Mt. Wuyi (1139 meters above sea level) and includes a thorough examination of the seasonal fluctuations in their composition, sources, and significant influencing factors. As a result of the air masses traveling mostly via northern heating zones, the total abundance of nine quantifiable NACs increased significantly in the winter (3.9 &plusmn; 1.5 ng m^-3) and autumn (2.1&plusmn; 0.94 ng m^-3), whereas it decreased in the spring (1.3 &plusmn; 0.75 ng m^-3) and summer (0.97 &plusmn; 0.36 ng m^-3). The most prevalent NAC species during the year was 4- nitrocatechol (25.8 %), followed by 5-nitroguaiacol (17.6 %). In addition, the majority of NACs (93 %) were influenced by coal, biomass, and petroleum combustion over the entire year, according to the results of structural equation modeling (SEM). Pollutant movement had a significant impact on the atmospheric NACs at the peak of Mt. Wuyi, especially in the winter (93.4 %) and spring (68.7 %). Long-range transport of nitration reactions was the dominant style in the transport process during the winter (33.7 %), while long-range transport of mixed sources was significant throughout the other seasons (14 %&ndash;37 %). In particular, for 4-nitrocatechol, NO₂ may enhance the generation of NACs with a major impact on their compositions. Under low-NO_x conditions, the formation of NACs was comparatively sensitive to NO₂, suggesting that NACs would become significant in the aerosol characteristics when nitrate concentrations decreased as a result of emission reduction measures.