In recent years, I have mainly worked on the two research areas: pulsar polarization and magnetic fields in galaxies. Together with my cooperators, we have observed about 150 pulsars in total and will do another 100 in near future. We did systematical studies on circular polarization of pulsars and obtained several intriguing results. Using pulsars as probes, we detected the magnetic field reversals from spiral arm to arm in our Galaxy. We found that the B-field has a bi-symmetric structure in the disk. We also obtained the unique measurements of the vertical component of the B-field in the solar vicinity. From the anti-symmetric distribution of Galactic rotation measure sky, we identified the B-field structure produced by A0 dynamo in the Galactic halo or thick disk. The magnetic fields in the disk of our Galaxy and M31 were found to be very extended. The spiral B-field we detected from NGC2997 suggests that there may be two kinds of dynamos operating in one galaxy.