An isocyanate composition according to the present invention contains an isocyanate compound of formula (1) and/or (2) (wherein R1 represents a hydrogen or a monovalent organic group, and R2 represents a monovalent organic group), and, relative to the total mass of the isocyanate compound in the composition, 1.0 ppm by mass to 10% by mass of a compound of formula (3): R13—(COO—R14)a (wherein R13 represents an organic group with a valence of a, R14 represents a monovalent organic group, and a represents an integer of 1 or 2), which is different from the isocyanate compound, and/or, 1.0 ppm by mass to 10% by mass of a compound having an UV absorption in an area of decamer or higher isocyanates in a measurement spectrum of gel permeation chromatography.