The work is focused on the role of single components of Vitamin B complex: pyridoxine, riboflavin, thiamine, and nicotinamide in the processes of growth and development of the human brain derived cells. We, also, have assayed the activity of Xanthine Oxidase in the presence of above mentioned subcomponents to delineate the possible mechanism of their action. Results indicate that the all components of Vitamin B complex might be responsible for cells' growth, maturation, proliferation. During early period of the cells' growth the most important components were thiamine and Pyridoxine, initiating cells' proliferation (number of the cells in one field: 2556, 17±355, 68, 2179,0±223,55, resp) vs control (1562,94±146,45), whereas during the late stages of maturation the most important components responsible for differentiation, were riboflavin and nicotinamide (3774.77± 188.41, 3558.82±152.90 resp. vs control 2905±263.75; p<0.035). In comparison with the all other subcomponents of Vitamin B complex only in pyridoxine containing samples, XO activity was specifically inhibited by allopurinol (percentile of inhibition 160,00±60,00 vs control 31,03±6,92, p<0,05). We have concluded that Pyridoxine might interact with XO and regulate its activity. All components of Vitamin B complex are able to initiate cells development and growth; however, they are supposed to be selectively utilized in time dependent manner to guarantee the highest efficiency of the cells development, maturation and proliferation