This research aims at developing original components of Decision Support System (DSS) in order to support the evaluation and selection of suppliers in multi products having limited capacity. To achieve this purpose, researchers have proposed three different models based on which suppliers allow selecting their own desired type of discount. Firstly based on the performed studies, some criteria have been suggested for evaluating the suppliers’ capability. These criteria will be selected by the buyer with respect to the purchase condition and type of the industry, and their importance level will be determined. Then based on multi-criteria decision models, evaluation of all the suppliers will be done. In this study fuzzy numbers are applied so as to translate qualitative criteria into quantitative one. Suppliers have been ranked according to the scores they have gained and the selection share of each from the whole quantity has been determined based on the multi-objective mathematical model. The existing model has exerted practical ways such as taking loans with determined interest as well as certain variables in order to compensate the shortage of budget the buyer encounters with. Outputs, which are, the selective suppliers and orders assigned to each of them are also to be considered by using Genetic Algorithm in MATLAB software for three parts in Emersan Company accordingly.