Magnetic field reversal may refer to:
- Geomagnetic reversal
- Brunhes–Matuyama reversal, approximately 780,000 years ago
- Gauss-Matuyama reversal, approximately 2.588 million years ago
- Jaramillo reversal, approximately one million years ago
- Laschamp event, a short reversal that occurred 41,000 years ago
- Reversal of the solar magnetic field
- Magnetization reversal, a process leading to a 180° reorientation of the magnetization vector with respect to its initial direction
- Polarity reversal (seismology), a local amplitude seismic anomaly