Objective To assess the composition of fatty acids in Beijing style finished dishes and enrich the database of Beijing characteristic food composition. Methods According to GB 5009.168—2016 National food safety standard-Determination of fatty acids in food, The contents of fat and fatty acids in meats, veggies, staples and snacks of Beijing style finished dishes were determined by gas chromatography, and compositions of fatty acids were evaluated. Results The content of total fatty acids in Beijing style finished dishes was about 0.070～36.3g/100g. among them, contents of saturated fatty acids, monounsaturated fatty acids and polyunsaturated fatty acids were respectively about 0.031～10.5, 0.007～16.0 and 0.012～16.2g/100g.It was about 0.763～36.3g/100g in meat dishes, Contents of fatty acids in vegetarian dishes, staples and snacks were respectively about1.40～18.0, 0.150～32.2, 0.070～29.5 g/100g.Among components of fatty acids, oleic acid, linoleic acid, palmitic acid and stearic acid were high in them. The saturated fatty acids were mainly palmitic acid and stearic acid, the monounsaturated fatty acids were mainly oleic acid, and the polyunsaturated fatty acids were mainly linoleic acid and linolenic acid. Conclusion The composition and content of fatty acids in Beijing-style finished dishes varied greatly, contents of saturated fatty acids, monounsaturated fatty acids and polyunsaturated fatty acids varied largely, trans fatty acids were also founded in some dishes.