Micro foam drilling fluid has irreplaceable advantages in reservoir protection, drilling speed, improve the cementing quality and leak plugging, especially suitable for the "three low" Daqing peripheral oilfield Haita area. Indoor the foaming agent, foam stabilizing agent were screened, Preferably choose the efficient composite foaming agent, stabilizer and thickener, the drilling fluid system is transformed into micro foam drilling fluid system. And evaluate the inhibition, anti temperature, anti pollution (anti clay, calcium, anti kerosene) reservoir protection capability, The micro foam drilling fluid leakage, oil reservoir protection, speed up mechanism and micro foam drilling fluid rheological characteristics were studied, Set up a specific rheological model of Micro Foam Drilling fluid, According to the characteristics of Gulong oilfield,R&D the calculation software of Micro Foam drilling fluid density changes with the temperature, pressure and provide guidance for safe drilling. Field application shows that the system has the advantages of simple preparation,convenient maintenance, easy transformation, drilling fluid properties can meet the requirements of drilling technology, To ensure the safe, fast, and high quality drilling of oil and gas,reduce pollution,improve the productivity of a single well.