The invention discloses a base moulding plastic mould for an electric room heater. The base moulding plastic mould of the electric room heater comprises a fixed die, a movable die, a feeding hole and a cooling water runner, wherein a fixed die plate of the fixed die is provided with a guide sleeve, a movable guide pillar is inserted into the guide sleeve, the guide pillar is fixed on a movable die plate of the movable die, and the movable die does open and close movement by virtue of the guide pillar; the movable die and the fixed die are correspondingly occluded into a moulding cavity, the moulding cavity is a thin plate cavity protruding upward, the front of the moulding cavity is provided with a circular boss cavity, eight screw mounting hole cavities are uniformly distributed on the circular boss cavity, the circular boss cavity is provided with one cylinder cavity at the center, the two sides of the cylinder cavity are provided with semicircle rotating sliding chute cavities, and multiple reinforcing rib cavities which are arranged in a radial shape from the center of the cylinder cavity to the outside are arranged at the concave surface side of the moulding cavity. By adopting the manner, a production process can be simplified and more human and material resources can be saved, so that the base moulding plastic mould disclosed by the invention is applicable to flow line production of a product, production cost is saved, and production efficiency of an enterprise is greatly improved.