Abstract: Development of Baolang oilfield is very difficult and reservoir damage is severe due to its specific reser-voir conditions.Better understandings are achieved in respect of reservoir physical properties,micro pore structure,wetting behaviors,relative permeability,water-flooding efficiency,reservoir sensitivity and oil and wa-ter properties on the basis of research on reservoir seep-age flow parameters at the initial stage of development in Baolang oilfield.The geologic factors that cause for-mation damage are also comprehensively analyzed.Clay stabilizer pretreatment should be performed in near well-bore formations before new well intervals being put into production to prevent clay minerals swelling and fine particles migration.Water injection rate should lower than4.5m/d.