The aim of this research was to investigate the relation between biological and mental functioning of a human. It has been carried out at the sample of 94 male subjects, 20 to 25 years of age, clinically in good health and positively selected considering the functions of cognitive processors and connative regulators by standard apparatus for biochemical blood analysis. Twelve haematological variables were tested, and by means of psychological tests six connative factors were determined suggested by Nebylitzin’s theory of neural system characteristics. At the level of cross-correlations of hematological and connative variables transformed in Qspleens, a rather high negative correlation of creatine kinase and neural system inhibition power is dominant, which is connected to important positive correlations of creatine kinase with the sensitivity and flexibility of neural system. This means, at least at the level of this analysis, that creatine kinase inhibits neural system inhibiting functions, but does not have any important impact on the power of activating functions, or the disbalance of excitation-inhibiting processes, which can be seen from its irrelevant correlations with the neural system activation power and with neuroticism and instability of neural system. However, neuroticism is considerably connected with alanin amino transferases and potassium, but these connections are numerically rather low. Other correlations of neuroticism with this set of haematological variables are not important, but there are still systematic negative correlations with hematocrit and thrombocyte measures; the fact that these correlations have just approximated the chosen level of importance can be a consequence of operational definition of neuroticism in Nebylitzin model, which similarly to Gilford model, actually treats neuroticism as a consequence of basic anxiety. As far as other correlations are concerned, only positive correlation between proteins and sensitivity of neural system is important; therefore, the sensitivity of neural system depends largely on convergent action of proteins and creatine kinase. The data were then processed by non-linear method of canonic correlation analysis, canonic analysis of co-variances and nuclear analysis. The results of all three analyses carried out converged towards the same conclusion: inhibitory power of neural system together with lowered sensitivity, flexibility and lower neurotic condition was under negative influence of creatine kinase, alanin amino transferase, potassium and proteins, while the inhibitory form of neuroticism was under lower but still considerable negative influence of all haematological factors, which were relevant for biological resistance of an organism. Three various and complex statistic procedures have been used in order to investigate in as much detail as possible the connection between the important biological characteristics of organism and personality characteristics. Such researches are rather rare and represent an important contribution to the knowledge concerning the relation between physiological and mental levels of human functioning.Na uzorku od 94 ispitanika muškog pola, od 20 do 25 godina, klinički zdravih i pozitivno selekcionisanih obzirom na funkcije kognitivnih procesora i konativnih regulatora analizirane su relacije 12 izabranih hematoloških varijabli i 6 konativnih faktora pretpostavljenih Nebilicinovom teorijom o karakteristikama nervnog sistema nelinearnim metodama kanoničke korelacijske analize, kanoničke analize kovarijansi i nuklearne analize. Rezultati sve tri provedene analize konvergirali su prema istom zaključku: inhibitorna snaga nervnog sistema, povezana sa smanjenom osetljivošću, fleksibilnošću i nižim neurotizmom, pod jakim je negativnim uticajem kreatin kinaze, alanin amino transferaze, kalijuma i belančevina, dok je inhibitorna forma neurotičnosti pod nešto manjim, ali još uvek znatnim negativnim uticajem svih hematoloških faktora od kojih zavisi biološka otpornost organizma. Tri različita i složena statistička postupka upotrebljena su da bi se što detaljnije ispitalo u kakvoj su vezi važne biološke karakteristike organizma i osobina ličnosti. Ovakva istraživanja su veoma retka i predstavljaju bitan doprinos u pravcu dolaženja do saznanja odnosu fiziološke i mentalne ravni ljudskog funkcionisanja