A water-based skin care agent (1) containing 4%-85% by mass water, 13%-80% by mass magnetic powder, and a thickener. The magnetic powder comprises a magnetic ferrite as the main component thereof and has a volume average particle diameter of 20-100 µm found from the particle diameter distribution obtained by the laser diffraction scattering method. The water-based skin care agent (1) may include a cosmetic component such as an ion introduction component (3). In addition, the water-based skin care agent (1) ideally includes 10%-45% by mass glycerin as a thickener.
