A radiation sensitive composition for color filters, which can provide red pixels having high transmittance and high contrast ratio and have rheological characteristics being suitable for the application of a large-sized substrate. The radiation sensitive composition comprises (A) a pigment, (B) a dispersant, (C) an alkali-soluble resin composed of a copolymer of (c1) a carboxyl group-containing unsaturated monomer containing (meth)acrylic acid, (c2) an N-substituted maleimide and (c3) at least one selected from the group consisting of styrene, &agr;-methylstyrene, p-hydroxy-&agr;-methylstyrene, methyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, allyl (meth)acrylate, benzyl (meth)acrylate, glycerol mono(meth)acrylate, polystyrene macromonomer and polymethyl methacrylate macromonomer, (D) a polyfunctional monomer, (E) a radiation sensitive radical generator and (F) a solvent, wherein the pigment (A) contains 20 wt% or more of C.I. Pigment Red 242 and has an average particle diameter "r" (nm) of 50 to 200.