The invention discloses a preparation method of a fire resistant cable for electric power transmission. By making full use of the fire resistant insulation principle of a mineral insulating cable, on the premise of not changing the fire resistant insulation principle, a copper pipe sheath in the mineral insulating cable is changed into a basalt fiber material coating with a higher melting point and a higher electrical insulating property, so that the fire resistant cable provided by the invention has higher fire resistance and high-temperature insulating property at combustion high temperature; moreover, an outer basalt fiber cloth cover is soft in texture and can be turned outward; before the filling of magnesia powder, the free end in the length direction of the outer basalt fiber cloth cover is turned outward, and the inside and outside are exchanged; in cooperation with a mould pipe, a very short to-be-rammed space is created in the mould pipe, then a ramming pipe or similar ramming device can smoothly go into/out of the mould pipe for ramming, and after the ramming, drawing or rolling is not needed; and therefore, the time and labor are saved, the production technology is simplified, the cost is remarkably lowered, and the production length of the fire resistant cable is not limited theoretically.