Heat treatment during storage is effective in delaying the ripening of fruit.In this study, an optimal pattern of heat treatment for tomatoes was investigated using an intelligent control technique consisting of neural network and genetic algorithm. An objective function was given by the reciprocal number of the color development from green to red for evaluating the ripening of tomatoes.The control process was divided into 8 steps.First, the color development was identified using neural network.Then, the set point of temperature which maximized the objective function at each of the 8 steps was sought through simulation of the identified model using genetic algorithm. The genetic algorithm allowed an optimal heat treatment to be successfully sought through simulation of an identified neural network model. The optimal heat treatment obtained here was intermittent, while the normal heat treatment was only one treatment at the first stage. Finally this optimal heat treatment was applied to an actual system.The results show that the optimal heat treatment indicates a better result in maintaining the color development of fruit than the conventional one.