A personalized meal planning method is provided. The method utilizes a food clustering technique to generate personalized meal plans. The method provides a food clustering stage and a food matching stage. The food clustering stage includes the following steps: input a personal nutrient goal; set a weight and a necessity value for each target nutrient feature; generate food clusters by applying a clustering algorithm; compute food ranking; and provide a diet recommendation. The food matching stage includes the following steps: select a food item to be replaced; determine a threshold of target similarity; and provide at least one replaceable food item. A personalized meal planning system is also provided.