To provide a stable aqueous ink for ink jet using dispersed colored fine particles showing high manufacturing stability and excellent dispersion stability and to provide a method of image formation showing excellent color reproducibility and stability by use of it.

The aqueous ink for ink jet contains colored fine particles each comprising a core particle having a colored material and a shell portion having a resin covering the core particle wherein the resin of the shell portion contains not less than 0.1 mass % to less than 50 mass % of a monomer unit having a hydroxy group in the molecule.