Abstract: Beginning with the very important research on oil and gas reservoir formation in petroleum geology this paper analyzes its histoy which is divided into three historical stages． The first stage from the end of 19th century to the early 1950s is represented by anticlinal theory or gravitational theory of oil and gas reservoirs． The second stagefrom the middle of 1950s to the end of 1970s is represented by the Tisso organic oil－generation theory oil and gas secondary migration and accumulation and continental petroleum geology theory in China． The third stage from 1980s to now is represented by reservoir characterization basin modeling reservoir geochemistry oil and gas system and reservoir－forming dynamics． The status and trend of oil and gas reservoir formation are discussed from the following aspects geothemal field and pressure field reservoir formation history oil and gas system reservoir forming dynamics and basin modeling．