Flame-retardant ethylene vinyl acetate copolymer (EVA) by silica gel-microencapsulated ammonium polyphosphate (MCAPP) and char-forming agent (CFA) have been cross linked by electron beam irradiation. The effects of electron beam irradiation on the electrical, thermal, mechanical, and flame-retardant properties of irradiated EVA composites were investigated. The thermal degradations of EVA/MCAPP/CFA composites were characterized by real-time Fourier transform infrared spectra and thermogravimetric analysis/infrared spectrometry. The results showed that a joint effect on the flame retardancy of EVA composites existed between the MCAPP and CFA. The volume resistivity and mechanical and thermal properties of the irradiated EVA composites were also evidently improved at appropriate irradiation dose as compared with those of unirradiated EVA composites, whereas the volatilized products for the combustible gases were decreased. Furthermore, the irradiated EVA composites can still pass UL-94 V-0 rating after treatment by water for 7 days at 50 degrees C, indicating excellent water resistance. This investigation provides a promising formulation for the halogen-free flame-retardant EVA with excellent properties.