The present paper aims to investigate the electrodeposition on steel substrate and the corrosion behavior of Zn-TiO2 nanocomposite coatings. Zn-TiO2 composite coatings were electrodeposited on OL 37 steel from an electrolyte containing ZnCl2, KCl, HBO3 (pH 5.7) brightening agents and dispersed nanosized TiO2. Corrosion measurements were performed in 0.2 g L-1 (NH4)(2)SO4 solution (pH 3) by using electrochemical methods (open-circuit potential measurements, polarization curves, electrochemical impedance spectroscopy). The results of electrochemical measurements were corroborated with those obtained by using non-electrochemical methods (X-ray diffraction, atomic force microscopy and scanning electron microscopy). The results indicate that the composite coatings exhibit higher corrosion resistance as compared to pure Zn coatings and a non-linear dependence of their polarization resistance on TiO2 concentration in the plating bath was found. The importance of TiO2 nature and concentration regarding the properties of the composite coatings was demonstrated.