Antenna elements (101, 102) used for multi-band antenna dual polarization include: four radiating elements (201), a balun element configured to feed power to the radiating elements (201), and a fastening plate (202) configured to fasten the balun element. The balun element includes two dielectric plates (203). Two signal transmission units (301), one feeding unit (401), and two filtering units (402) are printed on each dielectric plate (203). An LC resonant energy storage structure is constructed on the balun element by using the filtering units (402), and decoupling on a specific frequency band can be implemented by adjusting the filtering unit (402). Therefore, even if the antenna elements (101, 102) are applied to a scenario in which elements on different frequency bands work collaboratively, radiating elements (201) on different frequency bands are not coupled electromagnetically and strongly when the radiating elements are arranged closely.