To obtain the subject heat-resistant composition by including an ethylene-propylene-diene rubber (EPDM) and/or an ethylene-propylene rubber (EPM) and an ethylene-acrylate rubber (EAM) as rubber components in a specific proportion.

This composition comprises (A) an EPDM and/or an EPM and (B) an EAM in (95/5) to (5/95) weight ratio of the contents of the components A/B. The ratio of the ethylene/propylene of the component A is preferably (40/60) to (90/10) (weight ratio). The component B preferably has 40-90 wt.% of the methyl acrylate content and is preferably a binary rubber or a ternary rubber having a cross-linked site. An additive such as a filler, a softening agent, a foaming agent, a plasticizer, a lubricant, a tackifier, an antioxidant or an ultraviolet absorber can be compounded with the composition.