The utility model provides a mould of a carbon-free ladle wall brick, which relates to an improved carbon-free ladle wall brick mould. The utility model provides a mould which is practical and convenient to be used, is convenient to be dismantled, and is suitable for multi-variety small batch production of the ladle wall brick. The mould comprises a bottom plate. The structure key point is that a front lateral plate, a back lateral plate, a left lateral plate and a right lateral plate are arranged above the bottom plate symmetrically. The front lateral plate, the back lateral plate, the left lateral plate and the right lateral plate are respectively connected with the bottom plate. The edge of the front lateral plate is connected with the edge of the back lateral plate by bolts. A square brick core is arranged among the front lateral plate, the back lateral plate, the left lateral plate and the right lateral plate. The brick core is fixed on a notch of the bottom plate through a convex locating block at the bottom of the brick core.