Abstract: Based on the typical petrophysical properties and fluid parameters in Wellblock?Z32 in Fengcheng oilfield of Junggar basin, the real trajectories of dual?horizontal well pairs by steam?assisted gravity drainage (SAGD) proses are analyzed and the numerical simulation models for characterization of the lateral and vertical offset in horizontal interval as well as simultaneous lateral?vertical offsets are developed, and the SAGD production performance prediction and response correlation are conducted. The simulation results show that the lateral offset and vertical offset may cause reductions of the peak oil rate, oil recovery factor and oil steam ratio, of which the vertical offset has more impact on the SAGD response. The local vertical offset distance reduction may give rise to partial steam breakthrough in horizontal interval, therefore, during drilling process, the simultaneous reduction of vertical offset distance in the two ends of horizontal interval should be avoided, because when taking simultaneous offsets, the adverse impact on the production is much more than the simply adding of the impact of lateral offset and vertical offset, and the more bi?directional offset, the poorer the SAGD performance