Abstract: Reserve and production ratio is the ratio of the yearend remaining recoverable reserve to the annual output. This value is often mistaken for how long the existing reserve can last. The numerator and denominator of the ratio are variables under the influence of many factors. The changes in the oil and gas statistical figures (such as a certain kind of non-conventional oil and gas is included in the reserveproduction ratio) may cause the ratio to rise substantially. Generally speaking, the world oil reserve and production ratio is on the rise. It is 57.5 in 2013. The natural gas reserve and production ratio is also on the rise, reaching 63.1 in 2004, but it has dropped slightly since 2010. The average value is 58.3 in the past four years. China^’s oil reserve and production ratio reached its peak of 19.5 in 1984 and then declined to 12.2 in 2013. The country^’s natural gas reserve and production ratio climbed at the initial stage of rapid development, reaching 66.3 in 2002 and then was on the decline (particularly after 2006), reaching 29 in 2013. Generally speaking, China oil and gas reserve and production ratios are lower than the world^’s average, belonging the same level as the United States. The healthy oil and gas industrial development may be affected when the reserve and production ration is too high or too low. The reserve and production ratio can be lowered slightly if the resources are abundant with the market forces able to be mobilized for exploration in a short period of time. The study indicates that oil and gas used as main energy can last well into the second half of the 21st century.