Unmanned aerial vehicles (UAVs) are systems that can successfully fulfill many missions in commercial fields with their wide range of payload capacities, different performance features, and low operating costs. One of the areas that has become a trend in the use of UAVs is cargo transportation. As developed unmanned aerial vehicles in this area have given satisfactory results, the design approach in this area gained importance. The main objective of this study is to establish a parametric design methodology to initial weight determination of a quadrotor UAV to be used to carry lightweight urgent payload among close locations. In this study, after identifying the components that meet the mission requirements, main design parameters (masses of motor, propeller, frame, etc.) are determined and the relationships among these parameters were correlated with each other. By using these results, the iteration number and design duration are reduced.