Fish oocytes and embryos are complex cryobiological objects for which, successful cryopreservation has still not been achieved. This circumstance seriously restricts the potential of germplasm cryobanking in aquaculture and for the conservation of rare animal species. Vitrification is one of promising approach of modern cryobiology. To achieve vitrification, high concentrations of cryoprotectants and rapid freezing rates are required. The processes of vitrification are poorly studied in terms of microscopic structure and molecular dynamics. We aim to investigate microscopic water structure during cooling of cryoprotectant solutions formulated during our previous studies on fish embryo vitrification. The results of study will lead to better understanding of water structure in vitrified cryoprotectant solutions required for future progress in vitrification of complex biological objects.