The invention relates to a device (1) for measuring the state of polarization of an incident wave of frequency 10 GHz to 30 THz, comprising a field effect transistor (2), a reception antenna (3). According to the invention, the antenna parts (31, 33) detect a component of polarization of the wave, collinear with a direction (X) causing in the transistor (2) an alternating detection voltage (Us), the parts (32, 33) detect a component of polarization of the wave, collinear with a direction (Y) causing the appearance in the transistor (2) of an alternating detection voltage (Ud), the transistor (2) being designed to generate, as electrical detection signal (ΔU) between the source terminal (21) and the drain terminal (22), a DC detection voltage (ΔU) a part of which is determined by the state of elliptical polarization of the wave by interference in the transistor (2) between the alternating voltages (Us, Ud).