Abstract: Abstract:As one type of cements , laumonitide often develops in sandstone of Triassic Yanchang Formation in Ordos Basin and Jurassic Shaximiao Formation in Sichuan basin.Moreover the laumonitide is often dissolved by organic acid water to form lots of secondary pores. The practice of oil-gas exploration in Ordos Basin and Sichuan Basin confirms that secondary pores dissolved from laumonitide are major stored space of oil-gas. In the paper, with studying origin and distribution of laumonitide and the forming mechanism and distribution law of its secondary dissolved pore, it is considered that origin and distribution of laumonitide are controlled by sedimentary materials source and sedimentary micro-facies, and the distribution feature of secondary pores dissolved from laumonitide are controlled by the sources and migration pathway of organic-acid water