The present invention provides a better electromagnetic lens, a method for producing it and a lens antenna. The electromagnetic lens is a winded body made of a strip material. The dielectric constant of a dielectric material gradually changes in both a transverse direction and a longitudinal direction of the strip material. After the strip material is winded to be a winded body, the dielectric material is distributed in at least one artificially predetermined three-dimensional space range called a lens body inside the winded body. A part of the winded body besides the lens body is called a non-lens part. The dielectric constant of the lens body is not lower than that the dielectric constant of the non-lens part.