Abstract: Heavy oil as a kind of unconventional oil and gas resources has been the attentions of the geologists at home and in China, bohai bay basin, songliao basin in junggar basin and tarim basin found a lot of heavy heavy oil resources. It is estimated that the heavy oil resources in to be found up to 250×108 t, shows the broad prospects for exploration of heavy oil resources. But as a result of water oxidation, bacteria biodegradation, differential migration, high temperature pyrolysis and gas elution effect such as asphalt, oil occur gradually thick, always restricts the development of heavy oil.