The present invention discloses a booting process of crosslinked insulated cable aiming at solving technical problem of saving insulation layer and shielding material inside and outside. The invention comprises the following procedures: connecting booting wire with cable conductor and pull wire; closing lower sealer; starting producing line; adjusting core shift; injecting water-cooling pipeline full with cooling water; preheating electric heating pipeline; closing upper sealer; normal heating electric heating pipeline; injecting whole pipeline with nitrogen gas to the set pressure. Compared with prior art, lower sealer is closed first, water is poured into water-cooling pipeline, sampling point is sealed and wrapped adjusting core shift of insulation layer, water is prevented from entering into conductor after pipeline pressurized, 150 meter of drive line is saved after core shift at each starting, and insulation material is saved. Time to reach set temperature of normal production is relatively shortened after preheating to heating pipeline, hence thermal extension performance index of qualified conductor core is guaranteed.