Oil is an important energy and high-quality chemical raw materials, is an important strategic material people's livelihood, the oil industry is an important basic industry of the national economy. Since the reform and opening up, China's rapid economic development, the demand for energy is increasing. Oil as an important part of energy, primary energy consumption and production in our share of the rapid rise in the proportion and basically stable at a certain level, but also by the oil-exporting countries of the past into a major importer of oil, oil has become a constraint China's economic growth "bottleneck."
      China's oil exploration is still in the middle stage of maturity, oil reserves are still at a high base value of steady growth period, but more and more difficult exploration. China's main oil fields in general has entered a phase of diminishing, stable is becoming increasingly difficult, but there is still potential to be developed. Oil industry is a highly concentrated industry funding, but also a high-risk investment. Large foreign oil companies are almost vertically integrated, multinational business worldwide. The imbalance of the global economy, making the level of investment return on the big oil companies in different countries or regions vary. Throughout the production chain of the oil industry, the exploration and development of upstream, midstream pipeline transportation, refining and marketing and chemicals operations in downstream projects in different periods of return on investment level differences are very obvious, which determines the oil companies when making investment decisions great selectivity. How to make a reasonable determination of the scale of investment and capital investment, and seek a higher return on investment, is an issue of common concern to the oil companies.