Fatigue degree assessment has a significant role in guiding for training strategies. This paper collected heart rate data during the eight weeks of training and subjective questionnaire data of the fatigue degree of 31 swimmers.Among themheart rate data is composed of five data: the heart rate value when getting up early in the morning, the heart rate value during the training preparation, the heart rate value when intensity of training is the largest, the heart rate value when finishing the training and the heart rate value when finishing the recovering. Subjective questionnaire data of the fatigue degree is composed of three data: the negative evaluation value, the physical strength overdraft value and the reduced value of confidence degree. Through heart rate data of the entire process, explore its relationship with the three itemsÂÂ data of the fatigue degree, and establish a multiple linear regression model. After data test, model has good fitting degree and significance. It is reasonable to use the model to evaluate the fatigue degree of athletes.