The elastic modulus of corrosion product (Ecp) has been reported with significant variations in the literature. This study aims to investigate the Ecp of naturally-generated chloride-induced corrosion products formed in different concrete mixes. Microstructural characterization was conducted through nano-indentation, electron microscopy and Raman spectroscopy. The corrosion products were mainly composed of a goethite matrix with portions of maghemite, independently of the concrete composition. Microscopic analysis suggest that layers of corrosion products grow at different times and under different physico-chemical conditions. Our measurements showed that Ecp varied between 80−100 GPa, which can be suggested for numerical models of corrosion induced cracking.