The invention discloses a thermoplastic halogen-free flame-retardant polyphenyl ether elastomer cable material and a preparation method thereof. The cable material is used for a soft type electric wire and cable coating, and comprises the following components: polyphenyl ether resin powder, styrene-series elastomers, a plasticizer, a polyolefin elastomer, a compound phosphor-nitrogen flame retardant, an antioxidant and a lubricant. The material components are uniformly stirred in a high-speed mixer, extruded by a twin-screw extruder, pelletized in water, dried and then packaged to obtain a thermoplastic halogen-free flame-retardant polyphenyl ether elastomer cable material finished product. The thermoplastic halogen-free flame-retardant polyphenyl ether elastomer cable material designed by the invention has excellent performance such as good processing performance, halogen-free and flame-retardant performance, low density, high tensile strength, good scraping resistance, good softness, good low temperature resistance, capacity of being extruded at a processing temperature of 200 DEG C-280 DEG C and not decomposed, free of cracks on a sample sheet for seven days under a high-temperature high-humidity environment with 98% humidity and a temperature of 85 DEG C, free of precipitates on surface, and the like.