The relationship among electromyographic and psychological indices in athletes performing in tennis was found. Higher motor nerve conduction velocity response corresponded to a lower level of stress, a higher level of effectiveness of mental self-regulation and adaptability, a higher level of emotional stability. Statistically significant positive correlation between autonomic nervous system balance coefficient (by M.Lusher's test) and median motor nerve conduction velocity was revealed. This might be due to functional state of cardiovascular system. The obtained results can be used to correct the training process of young athletes.