A rapid method of the trim drag prediction for the blended-wing-body unmanned aerial vehicle(UAV)configuration is proposed.The method consists of four steps.The first step is to parameterizedly model the blended-wing-body UAV configuration;the second is to analyze the aerodynamics of the geometric model;the third is to create aerodynamic surrogate model;and the final step is to predict the trim drag using the surrogate model.Hence,a tool for trim drag prediction is developed by integration of the four steps.The impacts of the allocation of control surfaces,position of gravity center and planform parameters on the trim drag are investigated by using the tool.Results show that using the control surface in outer wing for trim has an advantage of lower trim drag,and the position of gravity center has a primary impact on the trim drag.Moreover,the planform has secondary impacts on the trim drag. A rapid method of the trim drag prediction for the blended-wing-body unmanned aerial vehicle (UAV) configuration is proposed. The second step is to parameterizedly model the blended-wing-body UAV configuration; the second is to analyze the aerodynamics of the geometric model; the third is to create aerodynamic surrogate model; and the final step is to predict the trim drag using the surrogate model .ence, a tool for trim drag prediction is developed by integration of the four steps The impacts of the allocation of control surfaces, position of gravity center and planform parameters on the trim drag are investigated by using the tool. Results show that using the control surface in outer wing for trim has an advantage of lower trim drag, and the position of gravity center has a primary impact on the trim drag. Moreover, the planform has secondary impacts on the trim drag.