Rett syndrome (RTT) is a rare neurodevelopmental disorder primarily affecting females, characterized by a spectrum of debilitating symptoms that impact neurological, cognitive, and motor functions. Eye-tracking technology (ETT) has emerged as a prominent tool in Augmentative and Alternative Communication (AAC) systems, particularly for neurological patients with motor and verbal impairments. This narrative review aimed to evaluate studies conducted on the use of ETT to improve cognitive abilities in girls with RTT and to examine its potential application. A review of the most recent empirical evidences was conducted. Some relevant contributions were highlighted and some useful ideas were detailed. Guidelines for research and practice were argued. The analyzed data demonstrated ETT's effectiveness in improving cognitive abilities in girls with RTT. ETT may be helpful in enhancing cognitive functioning in RTT individuals.