The degradation caused by corrosion of rebar in concrete structures is one of the most important issues to attract the attention of researchers focused on concrete durability. Penetration of chloride ions into concrete is one of the factors that can contribute to corrosion of rebar and consequently the strength of concrete structures as well as serviceability reduction. In this study, an experimental model was proposed to predict penetration of chloride ions into cracked concrete by performing non‐destructive tests. Tests were performed after 48‐months exposure of all samples to a harsh marine environment. For studying the influence of load‐induced cracks on the rebar corrosion, cracked and uncracked beams were tested. Results of this study demonstrated that by the increment of the crack width, corrosion of reinforcement increased and as a result, the probability of degradation of reinforced concrete beams increased accordingly. Furthermore, by the increment of crack width, their depth also increased which caused enhancement of crack depth on the rebar and easier access of chloride ions to the rebar.