An iso(thio)cyanate composition for an optical component has excellent storage stability. The iso(thio)cyanate composition includes an iso(thio)cyanate compound having two or more iso(thio)cyanate groups in a molecule, a phosphoric acid ester compound represented by general formula (1), and a phosphoric acid ester compound represented by general formula (2). A total amount of the phosphoric acid ester compounds is 1 ppm or greater and less than 25,000 ppm, based on the mass of the iso(thio)cyanate compound. A molar ratio of the phosphoric acid ester compound represented by general formula (1) and the phosphoric acid ester compound represented by general formula (2) is 30/70 to 70/30.