The purpose of the final project is to identify the influence of customer’s motivation, the perception of quality product, and attitude of customers toward purchasing decision for Kubota diezel engine brand and there are two variables which were most influential in the decision of purchasing. The methods of the collecting data used are interview, observation, and questionare. The type’s of the data are the qualitative and quantitative. The result of this study is that, the most influenced in purchase decision is mostly the perception of quality product and the second is attitude of customers. Then the result of Coefficient of Determination (Adjusted R Square) is 0,923 or 92,3% of increasing the purchasing decision is influenced by the perception product quality and customer’s attitude. The other 7,7% was influenced by another variable which wasn’t observed by the writer.