The enrichments of δ

13

C

δ

34

S and δD in crude oils gathered in various places

both in China and abroad

are studied and reported in this paper.For oils formed in salt lakes

their δ

13

C ranges from-24.70‰ to-28.30‰

averaging-25.86‰

δ

34

S from 12.30‰ to 1.00‰

averaging 7.57‰

and δDranges from-148‰ to-98‰

averaging-135.40‰.For oils formed in freshto brackish lakes

δ

13

C ranges from-24.61‰ to-29.60‰

averaging-27.49‰

δ

34

S from 17.02‰ to 4.51‰

averaging 10.48‰

and δD from-161‰ to-137‰

averaging-146.89‰.The enrichments of δ

13

C

δ

34

S and δD from salt lake oils and marine oils have some similarities.They are probably reflecting the primary types of organic matter as well as depositional environments

and may be influenced in some extent by the maturity of crude oil.