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Chemical composition of aerosols is of great concern in the Arctic because of its great influence on climate. In this communication, we report the physico-chemical properties of size-separated aerosol data archived at Gruvebadet lab in Ny-Ålesund (78.55°S, 11.55°E) as a part of the Indian Arctic Mission over the station ''Himadri'' in 2010. The results reveal that the mass-size distribution (MSD) of aerosol composition exhibits tri-modal distribution with coarse-mode (62%), fine-mode (32%) and weak nucleation-mode (6%) indicating dominance of natural sources over the study region. MSD of chemical components showed a significant contribution to coarse-mode particles for Ca2+, Mg2+, Na+ and Cl−; fine-mode particles for SO42−, NO3−, NH4+ and K+. The marine sources contributed maximum for SO42− (89%) and Mg2+ (44%) in the coarse fraction, and in the fine fraction, 31% to SO42− and 86% to Mg2+. Non-marine sources were major contributors (80 to 95%) in both mode fractions for Ca2+and K+. The estimated aerosol radiative forcing in the atmosphere of ∼3.21 W/m2 could be attributed to the loading of black carbon aerosols (62%) over the site. The backward trajectories show air masses from Canada and Greenland travelling from 6000 m elevation, bringing the pollutants to Ny-Ålesund and lower altitudes; the oceanic region within Arctic circle contributes more.