A fuel vapor adsorbing device (10, 60, 70, 70′, 80) for adsorbing residual fuel vapors that remain in an intake conduit (1, 2, 3, 4) of an induction system of an internal combustion engine when the internal combustion engine is stopped may include an adsorbing member (40, 40′) that is constructed to adsorb the residual fuel vapors and is disposed along an inner wall surface of the intake conduit. The adsorbing member is arranged and constructed to form a supplemental intake path (T, T′, T′″) between the adsorbing member and the inner wall surface of the intake conduit, so that intake air of the engine can flow through the supplemental intake path.