This dissertation presents the design, simulation, and execution of multi-unmanned aerial vehicles (UAV)-based cooperative source seeking and contour mapping with cyber-physical systems(CPS). Both fixed-wing UAVs and vertical takeoff and landing (VTOL) UAVs are developed as the flight platforms. Compared with single UAV, multi-UAV formation with advanced cooperative control strategies has more advantages for radiative source detection, especially in urgent tasks, for example, detecting nuclear radiation before deploying the salvage. A contour mapping algorithm for the nuclear radiation is proposed, and practical predefined waypoint-based formation flights are realized. Next, four scenarios are developed for multi-UAV-based cooperative source seeking and contour mapping of radiative signal fields. the fixed wing UAVs are more suitable for widespread detection, while VTOL UAVs are better for accurate detection. The flight control of each VTOL UAV is very critical, and the designed fractional order controller for pitch-loop control guarantees the stable flight. The conclusion of this dissertation and suggestions for future research are presented in the end.