A multicore mineral insulated cable with special-shaped structure belongs to the technical field of cables. The cable comprises a copper jacket as well as a magnesium oxide knob insulator and a copper conductor which are loaded in the copper jacket and is characterized in that the section of the copper conductor and the hole section of the magnesium oxide knob insulator are special-shaped structure which can be matched with each other, a plurality of copper conductors with special-shaped sections are respectively conducted into a plurality of special-shaped sectional holes of one magnesium oxide knob insulator. Special shapes include circle, sector, etc. The multicore mineral insulated cable has simple and reasonable structure and simple production and manufacture, and adopts the special-shaped structure to replace the combination of a plurality of single core cables, thus either the use amount of copper or the use amount of magnesium oxide powder can be greatly reduced and the production cost can be dramatically saved. During installation, the cable can be laid entirely, thus lowering the labor intensity of installation and reducing the space occupied by laying.