Superplasticity is the ability of the materials to under go large uniform strains prior to failure. Super plastic forming (SPF) is a near net-shape forming process used in aero-shape and automobile industries. Superplastic forming of conical shapes invariably poses a problem so far as large thickness variation is concerned, which occurs between apex and base of the cone. The observed variation is inevitable in Superplastic forming. In the present investigations a nearly uniform thickness could be achieved in a conical dome shape by pre-profiling of the initial blank, while the present experiments were carried out with a model material Sn-Pb alloy of 60%Sn and 40%Pb. The same is applicable for other superplasic materials e.g., Al-alloys, Ti-alloys etc. Initial experiments were carried out with uniformly disc shaped blanks, which have shown a large variation in thickness at different stages of forming of conical shapes. A simple mathematical manipulation leads to a design of profiled blank, which was thicker at centre and thinner at periphery. After forming up to an average strain of 0.54, the experiment was halted and reasonable uniformity of thickness was noted at this stage of forming.