Provided are a thermoplastic epoxy resin composition comprising (A) an epoxy compound having two epoxy groups in one molecule, (B) a compound having two phenolic hydroxyl groups in one molecule, and at least one compound selected from the group consisting of dihexylamine, diheptylamine, di(2-ethylhexyl)amine, N-ethylhexylamine, trihexylamine, dioctylamine, tri n-octylamine, N,N-dimethyl-n-octylamine, and N,N-dimethyldecylamine as (C) a curing accelerator, and a thermoplastic cured epoxy resin with transparency to visible light produced by curing the thermoplastic epoxy resin composition.