Abstract:  The reserve replacement rate is an important reflection of the management state of oil companies, especially in sustainable development. It is also an important indicator for oil companies to make annual plan and an important basis for branch company assessment. Because of many uncertain factors, it is very difficult to predict the reserve replacement rate. The connotation and characteristics of the SEC reserve replacement rate have been introduced in this paper, through forecasting three parts of the reserves, which include the annual “boundary extending and new discovery of new reserves”, “increasing recoverable reserves” and “correction” reserves. Then the SEC reserve replacement rate has been predicated. The method is simple and easy to operate. It has been applied in some oilfield to predict the SEC reserve replacement rate for the year 2011. Four main affecting factors for SEC reserves replacement rate have been discussed.