This paper applied the Data Mining theory and the iData Analyzer software to see if there was a correlation between the sales products and the operating items of the Farmers' Association Supermarkets of Hengchun of the 2nd half 2005, and to seek out if products are related to others from the categories of the largest items to the smallest. The research results showed that the freshness category has taken the highest consumer volume in comparison with the dried-food and daily commodity categories; except for the myriad types and items of the consumer products. However the consumer quantity of each item is quite small; there are correlations with dried-food, freshness and the daily commodities. After further treatment, we discovered that the freshness takes a larger percentage of sales volume, thus most correlations are related to it. The results of the study is that the Farmer's Supermarkets shall use the fresh goods to combine with the other categorical items in which they can be associated in order to promote the purchasing rate of the consumers and also decrease the stock volume, in order to assist in the improvement of current conditions of the Farmer's Association Supermarkets.