Abstract: Prior to making a decision to produce an isotope, it is necessary to investigate the economy of the production to understand and ensure its economic feasibility. A method of analyzing the production of a non-uranium isotope by centrifugation was presented in the paper. The relationship between the material recovery and the cascade relative total flow was obtained by using the theory of the model Q-cascade. Based on the data of the cost per unit SWU (separative work unit) openly available for uranium separation, to avoid involving many factors such as the separation unit cost and the personnel cost in the analysis, a simple formula for the cost analysis was derived under the assumption that the cost for separation was proportional to the scale of the production plant. The formula can be easily applied to the evaluation and optimization of the production cost of an isotope according to the material cost, unit separative cost for uranium separation, material recovery, etc. Taking the production of the lead isotope ²⁰⁸Pb as an example, the analysis process was explained. The results show that the cost evaluation is simple and easy to be carried out by using the method proposed here.