NH2 solid phase extraction cartridges were used to separate triglycerides and phospholipids from ruminant fatty acids and hydrogenated soybean oil and partially hydronated soybean oil were used as control groups. Then silver ion solid phase extraction columns were applied to elute trans octadecenoic acid isomers from triglycerides and phospholipids before detected by gas chromatography. Results showed three kinds of trans fatty acids were found in ruminant animals lipids and sheep lipids has higher trans fatty acids in total lipids and triglycerides with 7.64% and 7.38%， while beef fat has richest trans fatty acids in phospholipids with 5.89%. In addition， 9 types trans octadecenoic acid isomers were separated and detected by gas chromatography， in which the 11t18：1 was the richest isomer in ruminant animals lipids by the content of 30.33%-39.03% in trans octadecenoic acids of total lipids， 38.08%-45.09% in triglycerides and 27.10%-44.47% in phospholipids of ruminant animal lipids. PLS-DA analysis showed difference among three ruminant animals on trans fatty acids isomers， sheep lipids had higher 9t18：1 in triglycerides and 11t18：1 in phospholipids， beef lipids had richer 9t18：1 and 15t18：1 in phospholipids and milk fat had higher 12t18：1 and 16t18：1 in phospholipids. Thus phospholipids varied in ruminant animal lipids.