The invention provides an ink set having at least: a magenta ink containing at least a pigment; and a cyan ink containing at least a pigment. A ratio of M/C, in which M is the concentration of the pigment in the magenta ink, and C is the concentration of the pigment in the cyan ink, is 1.6 or more. A ratio of S2/S1, in which S2 is the solid content of an ink that has the largest solid content among the inks included in the ink set, and S1 is the solid content of an ink that has the smallest solid content among the inks included in the ink set, is 1.2 or less. The invention further provides an image forming method having applying the inks of the ink set onto a recording medium.