According to exploration maturity and oil/gas discoveries，plays are divided into three categories，namely play in appraisal，play in prelim inary prospecting，and play in regional prospecting.Appraisal parameters are selected according to probability of obtaining a discovery and strategic value of petroleum resources.Templates are built for evaluation of theses three types ofplays by using these parameters，and corresponding quantitative indices and parameter systems are also established.W ith theses templates，sim ilar plays in different regions can be appraised and selected on the same platform according to the same standards.