Abstract: The present invention provides an ultraviolet absorber containing a compound represented by the formula (A-1), wherein R represents a methyl group, an ethyl group, a propyl group, or an allyl group, and R1, R2, R3, and R4 may be the same or different, and each represent a hydrogen atom, a benzoyl group, a toluoyl group, a naphthoyl group, or an anthranoyl group. By adding the ultraviolet absorber to a composition for forming a resist under layer film, reflection can be suppressed particularly in lithography process by an ultraviolet laser, and a pattern profile can be improved without adverse effects on dry etching mask properties and adhesiveness to a resist pattern.