This study aims to modify the potato washing machine by adding cutting tool, because of the price of cutting machines offered is quite expensive with the capacity for middle to lower industry. In this study, there are 2 different types of machines used as benchmarking materials, namely the Multifunction Cutting machine and the Vegetable Cutter machine. Both types of machines will be analyzed and compared to the specifications of each machine. This machine modification process uses the benchmarking method, reverse engineering and the VDI 2221 method for the engineering design process. The final result of designing by adding cutting tool of a potato washing machine function with a quality similar to the existing machine. In this study, a calculation of the production costs and the selling price offered for 1 cutting machine was also carried out with the addition of a potato washer modification to be able to compare the price of this machine with the price of machines on the market. Modified cutting machines have a selling price that suits the middle to lower industry.