The invention discloses a preparation method of a new cable material. The preparation method of the new cable material comprises the following steps: a, uniformly mixing polyolefin resin, plasticizers, antiagers, antioxidants, halogen-free flame retardants and saturated fatty acid and then placing the mixture in a twin-screw extruder to be extruded to obtain a mixture I; b, mixing the mixture I with metal oxide, modified ultra-fine down powder, plasticizers and high-efficient catalysts and pouring into a high mixer to be stirred, mixing and plasticizing through the twin-screw extruder to extrude a mixture II; c, mixing the mixture II with coupling agents and cross-linking agents and then pouring into the high mixer to be stirred, mixing and plasticizing through the twin-screw extruder to extrude a mixture III; d, dispersing and mixing the mixture III with processing aids and nano-alloy and extruding to obtain the new cable material. The cable material prepared by the invention has excellent mechanical properties, good aging resistance and long service life.