In most chemical processes, there are more than two responses of interest, and we want to know the optimal levels of the factors（i.e., pressure, temperature, etc.） that influence the responses. This paper is to propose how to fit the multivariate response surfaces for a given set of data, and to propose how to analyse the data to obtain an optimal operating condition for the factors. To implement the proposed method in practice, a FORTRAN computer program was written and explained in this paper, lastly, an industrial example is illustrated to explain the proposed technique.