Background: Platinum compounds are a group of fundamental chemotherapeutics used in the treatment of solid tumors, but they are burdened by side effects, such as ototoxicity. The objective of this study was to evaluate the incidence of ototoxicity caused by platinum compounds and the risk factors affecting its appearance/progression. Methods: Data from 53 patients who received platinum compounds and who had been off therapy for at least 5 years were analyzed. We collected data relating to audiometry conducted annually from the end of treatment and for at least 5 subsequent years, as well as information concerning the oncological history and comorbidities. Results: At the end of the treatment, 17 patients (32.08%) presented ototoxicity, according to the Boston SIOP Ototoxicity Scale; the risk factors included a higher serum creatinine value at diagnosis, having undergone cranial radiotherapy, and needing magnesium supplementation. After 5 years from the end of the treatment, the number of patients with exhibiting ototoxicity was 31 (58.5%); the factors that influenced the onset/progression of the damage were having undergone radiotherapy (HR 1.23; p < 0.01) and having received therapy with aminoglycosides (HR 1.27; p < 0.01). Conclusions: Ototoxicity caused by platinum compounds can occur even after the conclusion of the treatments, and the factors affecting its progression are radiotherapy and the aminoglycosides therapy.