Abstract: A large amount of water was consumed during washing vegetables. The amount of water consumption is not only related to the washing principles but also to the mode of using water. In order to study the relationship between water consumption and mode of using water, the scientific evaluation method according to water consumption was established based on the washing tests before. Several washing modes were designed and mathematical models related to water turbidity changes caused by washing vegetables were demonstrated, which describe the process of vegetable washing. Based upon the analysis and calculation of water consumption for washing different dirty vegetables, it is proved that the mode of multi-trough washing can largely reduce the amount of water consumption. This study provides theoretical evidence for optimization of processes that will be designed and operated to wash vegetables.