AISI 316L samples were exposed for six months to Caribbean Sea water. The corrosion potential (Ecorr, o.c.p.) in the early stages showed variations to more or less negative values, considered as a consequence of the opposition between the pit nucleation and repassivation of active sites. However at the last four months maintained a tendency to less negatives values. Ecorr fluctuations, considered as electrochemical noise, were analyzed with the potential spectral density (PSD) vs. frequency in logarithmic scale. The negative PSD slope (β) indicated a release of spontaneous energy during the corrosion process. The calculated Hurst coefficient (Ĥ), based on β, suggested that initially the pit formation was controlled by fractional Gaussian noise (fGn) with the contribution of fractional Brownian motion (fBm) and at the later stages was dominated by fGn as a weakly persistent process. The results were correlated with the surface changes provided by SEM-EDX and XRD.