The formation of professional self-determination of Moscow college students (800 people) was studied. Reasons for choosing the profession, satisfaction with the organization of training, academic performance were estimated. The life­style and quality of life (MOS-SF-36), health, social adaptation were studied. It was shown that students with unshaped professional self-determination and random choice of profession had significantly more negative assessment of the learn­ing process and training, had reduced learning motivation, lower performance in theoretical and industrial training. They had more frequent manifestations of stress: worsening of mood and well-being, the higher incidence of acute respiratory infections, the increased risk of casual narcotization, the reduced quality of life. The inadequate professional choice negatively affects confidence in employment. Conclusions about the need for optimization of existing system of vocational guidance at the stage of school training are drawn.