Fatty acids (C14--C32) in the marine boundary layer were measured in aerosols that were collected over the northern North Pacific from October 1996 to June 1997. Concentrations of lower molecular weight (C14--C19) saturated fatty acids (LFAs, 0.8--24 ng m-3) showed a positive correlation with sea-salt concentrations, suggesting that LFAs are released from the ocean surface to the atmosphere with sea-salt particles. The averaged ratios of air/ in autumn, winter, spring and summer seasons were 1.8 (¿1.3) ¿ 10-4, 2.1 (¿1.3) ¿ 10-4, 3.7 (¿2.9) ¿ 10-4, and 4.6 (¿1.8) ¿ 10-4, respectively. The results indicate the seasonal variation of the sea-to-air flux of LFAs relative to that of sea salt with a maximum in spring to summer. The enhanced LFA flux was consistent with the satellite images of chlorophyll a over the northern North Pacific, which showed high biological productivity from spring to summer. On the basis of the ratios of air/, relative humidity, and modeled size distribution of sea-salt particles, the coverage of LFAs on sea-salt particles was estimated to range from 0.3 to 14%. This study suggests that the coverage of fatty acids, together with other film-forming materials, may have a significant effect on the physicochemical properties of aerosols, which may be affected by the high biological productivity in the high latitudinal ocean.