Abstract
In this paper, the fuzzy reasoning demand forecasting model is examined by using the business control data and meteorological factor during year. The analysis of sales of every day and the relation between the number of visitors and the meteorological factor is first tried here by applying a decentralized analysis, the principal component analysis is applied next, and the analysis of the relation of the meteorological factor of every day is tried. The fuzzy reasoning model which forecasts demand from these analysis results using the acquired combination is constructed.