Abstract: For a comprehensive understanding of bacterial community structure of the oil shale from Fushun west openpit mine in China and screening out best prime for PCRDGGE analysis of oil shale， an improved SDShighsalt extraction method was used to extract microbial total DNA from the oil shale. Fourset primers (968F/1401R， 338F/518R， 341F/907R and 1055F/1406R) of 16S rDNA high variable target regions， V6V8， V3， V8， V9， were compared to obtain the optimal target sequences suitable for PCRDGGE. The results from PCRDGGE patterns showed that fourset primers can amplify the target sequences， but different target sequences of primers have a significant effect on the detection of the bacterial diversity (P<0001). Compared with the other primers， 968F/1401R and 338F/518R are more suitable for the bacterial diversity analysis of oil shale samples due to higher fingerprint species richness and abundant bacteria group obtained from their PCRDGGE. The community structure of bacteria in oil shale is not much rich. Acinetobacter， Pseudomonas and Escherichia are the dominant bacterial communities， as well as some unidentified bacterium which belong to Pseudomonadales and Enterobacteriales.

Key words: oil shale, 16S rDNA, PCRDGGE, bacterial diversity, target sequences