To improve a property for removing formaldehyde without using latex including a carbonyl radical or the like by preparing a constituent material for removing formaldehyde by using specific semicarbazide.

A constituent material for removing formaldehyde, which is effective for a long time, is prepared by including semicarbazide introducing body of which average semicarbazide remaining cardinal numbers are more than 2.5. At this time, preferably the semicarbazide introducing body of which average semicarbazide remaining numbers are more than 2.5 is included in synthetic resins or in a forming body which do not include a carbonyl radical. Or when the synthetic resins or the forming body include the carbonyl radical, a volume more than three moles of semi radical in the semicarbazide introducing body is included against carbonyl radical of the synthetic resins or the forming body. Such semicarbazide introducing body constituent material is provided, for example, by acting a polyisocyanate compound and a hydrazine compound.