Abstract: In the light of the poor pertinence of plug-releasing method selection for injection wells, the Grade weighing comprehensive evaluation model is built and the calculating software is developed based on the field documents a-nalysis and the principle of probability statistics. The research shows that the coincidence ratio is 85. 43 % and the 5 injection wells results are the same between the calculation and the application. Accordingly this technology increases the pertinence and efficiency of different measures, drops unnecessary workload and construction expense, and improves the plug- releasing quality of injection wells and beneficial result of oilfield development.