Gene therapy is a promising treatment modality that is being explored for several inherited disorders. Multiple human gene therapy clinical trials are currently ongoing, but few are directed at hearing loss. Hearing loss is one of the most prevalent sensory disabilities in the world, and genetics play an important role in the pathophysiology of hearing loss. Gene therapy offers the possibility of restoring hearing by overcoming the functional deficits created by the underlying genetic mutations. In addition, gene therapy could potentially be used to induce hair cell regeneration by delivering genes that are critical to hair cell differentiation into the cochlea. In this review, we examine the promises and challenges of applying gene therapy to the cochlea. We also summarize recent studies that have applied gene therapy to animal models of hearing loss.