In order to not only obtain a higher frequency radiation but also scan its beam more widely, an active phased array using second harmonic generation is investigated. The active antenna consists of a patch antenna radiating the second harmonic wave, and a FET oscillator which plays owo roles in fundamental oscillator and frequency multiplying. The structure of a coupling network between the adjacent active antannas suitable for the phased array behavior is found by measuring the external quality factor looking at the coupling line of the active antenna. In the experiments, the radiated beam of the second harmonic waves from the two or three element active antenna array were scanned more widely than that in the case of the fundamantal wave radiation.