This article presents the study of the behaviour of reinforced concrete steels, used in constructions in Senegal, under the effect of corrosion. The study is carried out on locally manufactured steels from three (03) companies located in Senegal and on control bars imported from France. Type 1 (E1), Type 2 (E2) and Type 3 (E3) steels are locally manufactured and Type 4 (E4) steels come from France. For each type of steel, samples with diameters of 8 mm, 10 mm and 12 mm were used. Mass losses were evaluated after immersion of these samples in a corrosive solution. For each type of steel and for all the diameters studied, the corrosion rate that initiates cracking of the asphalt concrete was evaluated from the actual diameter of the bars and the thickness of the nominal coating. From the mass lost over time, correlations between duration and mass loss were established for all diameters of the different types of steel. These relationships made it possible to calculate the time required to reach the corrosion rate that initiates concrete cracking. The results indicate that 66.67% of the steels studied, of local manufacture, have a corrosion time that initiates cracking of concrete lower than that of the control bars imported from France. Type E1 steels with a diameter of 8 mm have a duration to reach the corrosion rate that causes cracking of concrete, equal to 49.71% of the duration of type E4 steels. These results indicate that the steels used in construction in Senegal do not have the same behaviour vis-à-vis corrosion.