Abstract: Based on genetic analysis of the Silurian bitumen from Yaogou and Devonian bitumen from Dangduogou in Songpan-Aba area,it was indicated that these bitumen samples were high maturated solid bitumen which sourced from the Silurian or Cambrian mudstones.They were the relict of the old oil pools which were destructed during the Early Hercynian movement.Formation of the bitumen was very complex.It might be the result of co-activity of cooling metamorphism and debitumination.Hydrocarbon could be generated from the bitumen as they were deeply re-buried.