The contactless angular position detection device includes a main casing (1) having a through opening (2) formed about a geometric axis (E) and a rotary element (3) to which a permanent magnet (4) is fixed. The rotary element (3) is mounted inside the main casing (1) to rotate with respect thereto about the geometric axis (E) Further, an electronic circuit 5 is mounted inside the main casing (1) and which includes a sensor (7) capable of detecting variations in the magnetic field produced by the permanent magnet (4) when rotating with respect to the main casing (1), a secondary casing (9) coupled to the main casing (1), and plug connection housed in or supported by the secondary casing (9) for connecting said electronic circuit 5 to the outside. The main casing (1) and secondary casing (9) are permanently and tightly attached.