Many children have benefited from cochlear implant device including those with congenital malformation of the inner ear. The results reported in children with malformed cochlea are very encouraging. We describe 2 cases of Mondini's malformation with severe sensorineural hearing loss. Cochlear implantation was performed and both of them underwent post-implantation speech rehabilitation. Post-implantation, both of them were noted to respond to external sound. But the second case developed facial twitching a few months after the device was switched on. It is important to evaluate the severity of the inner ear deformity and the other associated anomalies in pre-implantation radiological assessment in order to identify the problem that may complicate the surgery and subsequent patient management.