Now in current practice, the whole world is in the race of looking forward to earn maximum profit. A structural engineer’s goal is to prepare an ideal solution for the design of structurewhich istaken in use. In this paper, the present work deals with the aim of achieving the optimal and ideal design of reinforced concrete structures, reducing size and reinforcement for beam members and column members in multi - bay and multi - storey structures. Generally, in current practice to optimize cost, trial and error method has been used in which numbers of models are developed in software likes STAAD PRO, ETABS, STRUDS, etc. But this method is quite complex and having less accuracy thus there is a need to adopt one proper optimization technique which enables engineer to find and to prepare the ideal design for the structure which gives more accuracy. So, in this paper, for cost optimization of reinforced concrete (RC) framed structure, MINLP (Multi-Integer Non-Linear Programming) technique is adopted. Without changingthe functional criteria of beams and columns as per provisions given in IS456-2000, the structure is designed safely and economically. Programming of the design of structural elements beam and column has been done using MATLAB program. At the end of the study, the results of the optimized model using MINLP technique and manually optimized method are compared.This optimization task reduces 24.76% of the total approximate cost in beams and 13.79% in columns.