This article presents the test results of reinforced concrete beams with different percentages of reinforcement damage. One of the main causes of structural damage is corrosion. The main cause of corrosion is an aggressive environment, which can endanger the environmental ecology. During the study, the effect of damage to reinforced concrete beams was investigated. The beams were produced full-sized, 100x200x2100 mm. According to the research program, 6 beams were tested, including undamaged control samples with a single reinforcement bar of ∅20 mm – BC-1 and BC-2; samples with a reinforcement bar of ∅20 mm with about 10% damage – BD-3 and BD-4; samples with a reinforcement bar of ∅20 mm with about 20% damage – BD-5 and BD-6. The reinforcement bar was damaged before concreting the samples. As a result, it was determined that a reduction in the bearing- -capacity of the reinforced concrete beams depended on the percentage of damage to the reinforcement bar.