Purpose: The aim of this study was to assess the effect of a palatal lift prosthesis (PLP) on the speech intelligibility of cleft palate patients treated with pharyngeal flap surgery, the minimum duration required for improvement in nasality, and the sustenance of speech improvement after removing the appliance. Materials and Methods: Seven patients ranging between 16 and 26 years of age were recruited for this study. These subjects had velopharyngeal dysfunction secondary to a surgically corrected cleft palate, which failed to improve following pharyngeal flap surgery. A PLP was given to these patients and improvements in speech intelligibility were assessed using two speech examinations: perceptual analysis and nasometry. The nasal resonance, nasal air emission, and articulation were measured prior to the insertion of the prosthesis and at the end of every month for the next 3 months, following which the prosthesis was removed and the tests were repeated. Results: There was a statistically significant decrease in nasalance percentage at the end of the 3 months, and it was found that this improvement in speech persisted even after the removal of the prosthesis. Conclusions: A PLP, when used for a minimum duration of 3 months, causes a significant decrease in nasal resonance, thereby improving speech intelligibility in patients who failed to see improvement following pharyngeal flap surgery for velopharyngeal incompetence.