A system and a method for drone detection and collision avoidance, particularly for use in an aircraft, is provided. The system includes, but is not limited to a sensor, a processor, and an avoidance unit comprising a control unit. The sensor is configured to detect a drone signal in a predetermined space and to transmit the drone signal to the processor. The processor is configured to determine the presence of a drone in the predetermined space based on the drone signal. The processor is configured to transmit a command to the avoidance unit when the processor determines the presence of a drone. The control unit is configured to receive the command and to generate a warning signal in response to receiving the command.