Abstract Tetramethyl orthosilicate and triethoxyphenylsilane, which contains hydrophobic phenyl groups, were used as a silica (SiO2) source in a modified ligand-assisted reprecipitation synthesis approach for the fabrication of water-stable perovskite nanocrystals. Hydrolysis-condensation reaction of tetramethyl orthosilicate and triethoxyphenylsilane results in a formation of 3D siloxane network. Employing triethoxyphenylsilane in the synthesis enhances the hydrophobic properties of the SiO2 shell, which increases the stability of perovskites in aqueous medium. The stability of the CsPbBr3@SiO2 nanocrystals was estimated after 24 h of water exposure by the photoluminescence measurements at different time points. The synthesized CsPbBr3@SiO2 nanocrystals were visualized during in vitro experiments with murine melanoma B16-F10 cells. Hence, the potential of CsPbBr@SiO2 nanocrystals for bioimaging purposes was observed.