Abstract: LD oilfield is an extra-heavy oil reservoir, it has some problems such as deep burial, large viscosity, high reservoir pressure and complex reservoir mode and there is no development experience to learn from. Therefore, to solve the problem of thermal recovery mode selection, a high temperature-high pressure sand-packed model was built, and two different steam assisted gravity drainage(SAGD) development methods were studied by 3D physical simulation experiments. The results indicated that the thermal recover method by steam stimulation development was used first, then by SAGD timely, which could effectively use the characters of large volume at low pressure and high enthalpy value in steam, and take full advantages of SAGD method. And the ultimate recovery rate is higher than that of directly using SAGD development at oil reservoir pressure, and the stimulation thermal recovery rate increased by 19.8%.