The aim of this study was to analyze the wide frequency range of EEG-parameters to estimate a possible functional importance of different EEG-components to reach the relaxation state. Sixty five subjects 17 to 20 years old were involved in the investigation. The relaxation session with monopolar EEG-registration and autonomic parameters recording was conducted to each subject. Significant changes in all analyzed EEG-bands were observed during relaxation. Two types of changes of EEG-coherence were distinguished by wakefulness-relaxation shift of state, and correlation of the type of dynamic with LF/HF ratio were discovered.