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Observations of organic compounds associated with natural sources are scarce in Antarctica, which limits our understanding of their sources and formation processes over the pristine region. Summertime Antarctic PM10 samples collected from Bharati station were studied for a homologous series of dicarboxylic acids (C2‐C12), ω‐oxoacids (C2‐C9), α‐dicarbonyls (C2‐C3) as well as citric and pyruvic acids by employing a water‐extraction followed by dibutyl ester derivatization technique and analyzed using capillary gas chromatography (GC). Results show that succinic (C4) and citric acids are the foremost abundant among the measured organic acids followed by glyoxylic (ωC2), azelaic (C9), and adipic (C6) acids. Such a typical molecular distribution of organic acids suggests the dominance of natural sources over the Antarctic. Two distinct air masses arrived from different altitudes, high and low altitude‐troposphere (HTAs and LTAs), showed a significant difference in mass concentrations of organic acids with higher values in LTAs. Total diacids‐C accounted for ∼9% of total carbon in HTAs, which is linked to chemical aging during long‐range transport. The higher abundance of C4 and citric acids are likely produced through secondary photooxidation of marine‐derived organic precursors, such as unsaturated fatty acids, phenolic, and biogenic isoprene compounds enriched in sea‐surface microlayer, via sea‐to‐air emission as confirmed by the significant (p < 0.05) correlations among the organic tracer compounds. Minor concentrations of oxalic and malonic (C2 and C3) acids were attributed to photo iron‐complex reactions in the aqueous‐phase atmosphere. These findings may help in reducing model uncertainties and present new insights into the secondary formation of organic aerosols in the polar environment. Plain Language Summary: Antarctica is Earth's southernmost continent surrounded by Southern Ocean where continental transport of anthropogenic pollutants is trivial. In this study, we studied homologous series of dicarboxylic acids and related organic compounds were determined in PM10 collected at Indian Antarctic research station, Bharati, during austral summer (December 2017 to February 2018). We found a typical molecular distribution, characterized by high abundances of succinic and citric acids followed by glyoxalic and adipic acids, which is completely different from the continental urban and marine aerosols. We also observed significant depletion of oxalic and malonic acids attributed to the photo Fe‐complex reactions in the aqueous‐phase atmosphere during summer. High abundances of succinic and citric acids in summertime demonstrate that the secondary formation of organic aerosols are largely contributed from the marine derived biogenic organic matter via sea‐to‐air emissions followed by photooxidation processes in the pristine Antarctic environment. Since diacids are highly water‐soluble in nature, the measured organic compounds in this study have significant implications toward cloud activation properties such as their lifetime and albedo in the pristine Antarctic environment. Key Points: Homologous series of diacids and related compounds in PM10 were studied at Bharati Station, Antarctic in summerMolecular distribution was characterized by the predominance of succinic and citric acids followed by Glyoxylic acidPhoto‐oxidation of marine‐derived organic precursors via sea‐to‐air emission was the major source of diacids in summer [ABSTRACT FROM AUTHOR]