An MR sensor includes a first shielding layer, a second shielding layer, an MR element formed therebetween, and a pair of hard magnet layers respectively placed on two sides of the MR element. The MR element includes an AFM layer formed on the first shielding layer, a pinned layer formed on the AFM layer and a free layer formed between the pinned layer and the second shielding layer. The free layer is funnel-shaped, which has a first edge facing an air bearing surface and a second edge opposite the first edge, and the first edge has a narrower width than that of the second edge. The MR sensor can improve MR height control performance, and improve the ESD performance and decrease the PCN and RTN and, in turn, get a more stable performance. The present invention also discloses a magnetic head, an HGA and a disk drive unit.