The surgical approach for the correction of residual velopharyngeal insufficiency requiring secondary surgery at Chang Gung Memorial Hospital is the modified Furlow palatoplasty with pharyngeal flap (mFP-PF). The aim of this study was to describe the mFP-PF technique and to determine the results obtained with regard to improvements in velopharyngeal function in patients undergoing this surgery. This retrospective analysis included 58 non-syndromic patients treated during the period 1992-2015 who complained of hypernasal speech after primary cleft palate repair and failed postoperative speech therapy. All of them underwent mFP-PF surgery. Preoperative and postoperative perceptual speech assessment results were obtained. The male to female ratio in the study group was 1.2:1, and the mean patient age at the time of surgery was 8.27 years. The patients underwent nasoendoscopic examination and the velar closing ratio was categorized as 0.1-0.4 in 53.4% and 0.5-0.7 in 46.6%. The assessment of speech after mFP-PF showed statistically significant changes for all perceptual speech outcomes. The incidence of repeat surgery was 3.4%. This study revealed that 96.6% of patients did not require second surgery for velopharyngeal insufficiency. Further studies on obstructive sleep apnoea in post-mFP-PF patients and improvements to the surgical technique should be considered.