The purpose of this paper is to evaluate the accuracy of input coefficients which are usually estimated by various non-survey methods. The resulting analysis showed that there were considerable differences employed. One of the interesting findings was that the simple LQ method was shown to be better then the other non-survey methods with respect to the degree of accuracy. And from a sensitivity analysis which was to show the effect of changes in input coefficients on the level of production by industry, an increase of 10% in the value of input coefficient (machinary and equipment setor) resulted up to 500billion Won in GRP for the case region. Therfore one of the implications which we can derive from the resulting analysis is that it necessary to pay attention to the key coefficients first to save out time and money, while retaining a certain level of accuracy. One thing to be noted, however, is that the key coefficients but the total effects which are calculated through the Leontief inverse matrices. Therfore to enhance the accuracty of input coefficients estimated by nonsurvey methods it is required to handle the relevant setoral data more carefully or to employ semi-survey method in part.