Introduction:
The purpose of the research was to provide a comparative characteristic of the dynamics of psychophysiological functions and indicators of physical and technical readiness of young footballers aged 12–13 and 15–16 years during 3 months of training.

Methods:
The study involved 24 football players; 12 were 12–13 years old, 12 were 15–16 years old. Parameters characteristic of determining the psychophysiological status, indicators of the nervous system work capacity, and attention indicators were analysed with the help of computer programs for psychophysiological testing. Also, the level of physical preparedness (60-m running, 1000-m running, shuttle running, pull-ups, standing long jump), and of technical preparedness (juggling, running throw) were established. Testing was carried out at the beginning of the preparatory period and at the beginning of the competition period of an annual training process cycle. The gap between the tests was 3 months.

Results:
Changes of psychophysiological indicators and indicators of physical and technical fitness that occurred in the observed period were more expressed among the 12–13 years old football players than in those aged 15–16 years.

Conclusions:
At the age of 12–13 years, emphasis should be put on the development of psychophysiological functions since at an older age the level of these functions is more difficult to influence, which can be decisive for the perfection of the athlete in football.