Abstract: The oil from changbai red pine seeds by mechanical hydraulic cold pressing technology extraction method was studied. Single factors including pressure, temperature, press/stop cycle were tested. Optimal extraction conditions were:upper pressure of 15MPa;temperature of 45℃, press cycle of 4min and stop cycle of 9min. Under this condition, the yield of the red pine nut oil was 60.3%. Aliphatic acid composition of red pine seed oil was analysed. Eight kinds of aliphatic acids were determined. The result of the fatty acid contained palmitic acid, linoleic acid, oleic acid, stearic acid, eicosatrienoic acid, eicosadienoic acid, eicosenoic acid, twenty carbonate. The content in fatty acid were 4.08%, 18.13%, 11.48%, 2.39%, 0.87%, 0.88%, 1.04%, 1.44%.