Abstract: Silane-crosslinked halogen-free flame-retardant poly(ethylene-octene) elastomer(POE) compounds were prepared through a two-step melt-compounding method using Mg(OH)2 and Al(OH)3 as flame retardants, and its grafting rate was investigated in terms of different silanes and initiators. Mechanical properties, hot elongation performance, thermal decomposition behaviors and flame-retardant properties of the compounds were investigated by using a universal testing machine, a hot elongation tester, a thermogravimeter and a limiting oxygen index instrument. The results indicated that the silane-crosslinked POE initiated by dicumyl peroxide achieved a higher cross-linking degree than that by benzoyl peroxide. The crosslinking feasibility of POE with silane-crosslinking agents is in the order of vinyl trimethoxysilane>vinyl triethoxysilane>γ-methacryloxypropyltrimethoxysilane. The silane-crosslinked flame-retardant POE achieved a higher limiting oxygen index and better mechanical properties than uncrosslinked ones. Moreover, POE/Mg(OH)2 compound obtained a higher char yield than POE/Al(OH)3 ones. The silane-crosslinked flame-retardant POE also presented more residual mass than uncrosslinked ones.