The methodical system aimed at forming swimming skills of the cadets majoring in marine profile in the process of training and improving has been presented in the paper. The article discusses a modern theoretical substantiation, a detailed development of the methodical system of the formation of young people’s motor skills in navigation (young people being of different age and gender) in the process of professional training and improvement under conditions of the sea-based national and international experience. The content of conducting training sessions on the reduced/intense content which extends cadets' abilities in the training process, including compulsory, additional and separate classes on Physical Education and Sports within 5 stages with the fulfillment of home tasks has been given: development of the forces of abdominal muscles, arms and legs as well as flexibility in the joints of limbs, spine and trunk, as the most backward. The initial stage of training the cadets' swimming skills accounts to 4/6 compulsory, 4/6 additional and 4/6 independent classes – I semester, the loading volume for girls/young men corresponds to 500/700 m (the duration is 60 min, the intensity of heart rate accounts to 120-144 beats/min); the stage aimed at the in-depth formation of their swimming skills corresponds to 4/8 compulsory, 4/8 additional and 4/8 independent classes – II semester, the loading volume for girls/young men accounts to 600/800 meters, the duration is 60 minutes, the intensity of heart rate equals to 132-150 beats/min; the stage aimed at the initial improvement of their swimming skills involves 4/10 compulsory, 4/10 of additional, 4/10 independent classes in II semester, the loading volume for girls/young men accounts up to 700/900 m., the duration of training is more than 60 min, the intensity of heart rate corresponds to 144-162 beats/min; the stage aimed at the in-depth improvement of swimming skills involves 4/12 compulsory, 4/12 additional, 4/12 independent classes in IV semesters, the loading volume of swimming for girls/boys accounts up to 800/1000 m, the intensity of heart rate equals to 150-168 beats/min, during classes, the training takes over 50/60 minutes; the stage of the in-depth improvement of sports swimming skills includes 4/12 compulsory, 4/12 additional, 4/12 independent classes within I-IV semesters, the loading volume of swimming for girls/boys accounts up to 1000-1200 m, the intensity of heart rate corresponds to 162-180 beats/min, during the sessions, 60-70 minutes is the time given to the national swimming team.