Abstract：In order to reduce the risk of the pilot tests in microbial enhanced oil recovery and to develop scientific procedures, the parameters of in-situ microbial enhanced oil recovery projects should be investigated, including injection volume, injection concentration, injection patterns and enhanced oil production. The current field application of exogenous microbial enhanced water-flooding is in a developing stage. The injection volume ranges from 0.002 to 0.007PV (Pore Volume). The average microbial concentration is between 1% and 3%. The main injection patterns are of multi-cycle injection and slug injection, with good performancel. However, there are still some issues that require further explorations. In view of the present domestic situation about exogenous microbial enhanced water-flooding pilot tests, the active bacteria are advised to be selected by using advanced microbial technologies and by developing cost-effective nutrient package. Moreover, for specific reservoirs to choose profile modification and water-flooding, throughput and water-flooding in combination, it is necessary to combine indigenous and exogenous microorganisms. The application of exogenous microbial enhanced water-flooding should be improved further by changing injection water and biological inhibition to keep the continuity of microbial enhanced oil recovery.