Abstract: Based on the design requirements for flame-retardant cables in first level locations in DBJ/T 15-226—2021, characteristics of flame-retardant cables, and installation and operation environment in building engineering, a fire-resistant cable that met B₁ level of combustion performance and class A of bundle flame-retardant was designed and developed. Tests showed that the sheath was made of ethylene vinyl acetate copolymer and polyolefin thermoplastic elastomer as the base material, a certain proportion of montmorillonite with quaternary ammonium cation organic intercalation nano lamellar structure as the main carbon forming agent, mica powder, wollastonite and white carbon black as the ceramic skeleton, and a small amount of ceramic zinc borate as the high flame retardant and low heat release polyolefin sheath material. During combustion process, flame-retardant and fireresistant cables made by extrusion had characteristics such as no dripping objects, easy carbonization, non combustion support, and high flame retardancy, which could meet the high requirements for flame retardancy and fire resistance in construction industry.