Precipitation samples were collected in two different locations (Gávea and Serra dos Órgãos National Park - PARNASO) in the state of Rio de Janeiro, from April 2022 to April 2023. The samples were analyzed for ionic constituents by ionchromatography (IC) and to trace elements by ICP-MS to determine their concentrations and identify potential sources. The ion concentration (microequivalents L-1) of the Gávea samples was (oxalate) < (fluoride)< (malonate)< (bromide)< (acetate)< (sulfate)< (nitrate) < (chloride) and (potassium) < (magnesium) < (ammonium) < (calcium) < (sodium), while in PARNASO it was (bromide)< (oxalate)<(acetate)< (sulfate) < (nitrate) < (phosphate)< Cl and (calcium) < (magnesium) < (sulfate) < (potassium) < (sodium). The concentration (milligram per liter) of the trace elements in Gávea was (chrome) = (nickel)= (tin) < (manganese) < (copper)< (iron) < (lead) < (zinc), while in PARNASO it was (chrome) < (manganese) < (nickel) < (iron) < (tin)< (lead)< (copper) <(zinc). The samples from Gávea had an average pH of 5.73 and an average conductivity of 21.9 (microsiemens) cm-1, while those from PARNASO had a pH of 6.05 and a conductivityof 21.4 (microsiemens) cm-1. (sodium) e (chloride) were the most abundant ions in precipitation in bothlocations, having their origin strongly associated with sea spray. Significant correlations, enrichment factors, non-marine fractions and source fractio nation were performed to suggest the origin of the determined ionic species. The urban region of Gávea suffered a greater impact fro man thropogenic sources (52 percent), while the preserved region of PARNASO from natural sources (62 percent). The main trace elements were evaluated based on comparison with previous studies in the literature. (Tin) and (lead) have been linked to wear on vehicle components, fuel additives, and traffic. The increases in (iron), (nickel) and (zinc) in PARNASO suggested the contribution, respectively, of soil, liquid fuels/coal and geological plant materials/micronutrients. Thus, the effectiveness of rainwater as another tool for assessing air quality in a region was confirmed. Furthermore, it was proven, as expected, that pollution in Gávea was greater than in PARNASO.