MDM is a trade cooperative that has a business unit that provides healthy food for consumers around the Andalas University campus. So far, the selection of suppliers who supply goods to stores is only based on the trust of both parties, the principles of mutual acquaintance and kinship. The problems that arise from a process like this are the lack of the right supplier so that goods are not available all the time, relatively higher prices, late delivery and sometimes there are goods with poor quality. Therefore we need a GDSS that is able to overcome these problems. This GDSS helps decision making in determining the right supplier to the stores owned by MDM Cooperative. The methods used are AHP, TOPSIS and BORDA involving six criteria and five tested alternatives. This GDSS also involves three decision makers, namely the head of the cooperative, the deputy and the treasurer. The results of this prototype are able to show the best alternative that is selected based on the ranking results.