In recent years the unmanned aerial vehicles (UAVs) became important assets for military and civil use. In our master thesis we developed a system for marker detection and tracking that enables landing of a UAV without a parachute. The current UAV is limited to landing with a parachute, which makes it difficult to land on moving platforms and small areas. The goal was to develop a system that can help the UAV to land into the net markerd with a purposely designed marker. The developed system was evaluated on captured videos that simulate the real environment. Results have shown that the system works well under different circumstances such as various angles, distances, illuminations, blurriness, surrounding areas and fogginess.