Purpose: To study the audiological, rehabilitative and cognitive outcomes of cochlear implantation in patients with Fabry disease (FD).Method: This is a retrospective case study. Two adults with progressive hearing loss were followed up for over 3 years.Results: The patients had progressive hearing loss from the first decade of life. Preoperative evaluations indicated delays in speech perception and cognitive skills due to hearing loss. There was a significant increase in hearing thresholds and speech perception in both patients after the cochlear implantation. The cognitive skills and memory skills of the patient who started using the cochlear implant later in life continued to lag.Conclusion: In FD, hearing loss should be closely monitored and appropriate interventions should be selected early. Two patients from the same family showed the strong impact of early intervention on speech perception and cognitive skills. The study aimed to emphasize the necessity of speech perception and cognitive skills assessment during the follow-up of patients with FD.