A thermosetting epoxy resin composition can be cured rapidly at low temperature with an aluminum chelate-based latent curing agent without the use of a cycloaliphatic epoxy compound. The thermosetting epoxy resin composition includes an aluminum chelate-based latent curing agent, a silanol compound of the formula (A), and a glycidyl ether-type epoxy resin: (Ar)mSi(OH)n  (A) wherein Ar is an optionally substituted aryl group, and m is 2 or 3, provided that the sum of m and n is 4. Examples of the silanol compound of the formula (A) include triphenylsilanol, diphenylsilanol, and the like.