A flexible printed circuit board having an integrated shield, a circuit based thereon, and a hearing aid having the circuit, are provided. The flexible printed circuit board includes a mount layer, a metallization layer and a shielding layer for shielding against electromagnetic interference influences. It can be bent about a respective bending axis in at least two different bending areas, in which the two bending axes are at an angle of at least 45 degrees to one another. The shielding layer extends at least over the two bending areas. A circuit based on the printed circuit board can be fitted with electronic components in at least one circuit area and can be bent in the bending areas in such a way that the circuit area is shielded by the shielding layer against electromagnetic interference influences in at least three spatial directions which are substantially at right angles to one another.