[en] Highlights: • Titanium oxo-alkoxy clusters have radius 1.6 nm in 1- and 2-propanol solvents. • Titanium oxo-alkoxy clusters form nanoparticles with radius 1.9 nm in 1-propanol. • Titanium oxo-alkoxy clusters form nanoparticles with radius 2.6 nm in 2-propanol. • Growth kinetics of nanoparticles depends on the solvent nature. The nucleation-growth of titanium oxo-alkoxy (TOA) nanoparticles was studied in n-propanol and isopropanol solvents. A common feature is quasi-instantaneous appearance of stable clusters with the hydrodynamic radius 1.6 nm, which form nanoparticles aggregated during the induction period. In contrast to clusters, the nanoparticle size and growth kinetics were affected by solvent: their size was 3.8 nm in n-propanol and 5.2 nm in isopropanol and the growth kinetics in isopropanol was significantly faster. The results suggest that the stability of the growing TOA units decreases with an increase of size, supporting the hierarchical model of the sol-gel growth.