The association between velopharyngeal function, craniofacial morphology and adenoidectomy was investigated using 27 craniofacial and nasopharyngeal variables taken from lateral cephalograms. The sample consisted of 96 boys with cleft palates with or without cleft lips. They were examined at 6 years of age when cephalograms were obtained and perceptual speech assessments were performed. The subjects were divided into three groups: (1) velopharyngeal competence (VPC, n = 45); (2) mild incompetence not requiring velopharyngoplasty (VPI, n = 36); and (3) previous incompetence operated on with velopharyngoplasty ad modum Hoenig (VPP, n = 15) before the 6-year examination. The groups were further divided into two subgroups according to previous adenoidectomy (Ad+, Ad-). The cranial base, size and interrelationship of the maxilla and mandible and their relationship to the cranial base or the bony nasopharynx did not differ among the VPC, VPI and VPP groups. The sagittal depth of the nasopharyngeal airway (Pm-ad1, Pm-ad2, Pm-ad3) was significantly wider in the VPP group than in the the VPC and VPI groups. The previous adenoidectomy decreased the thickness of the posterior pharyngeal wall (ad1-Ba, ad2-so) and thus increased airway size. The length of the velum did not differ between the three groups or their subgroups with and without adenoidectomy. The results showed that adenoidectomy is a risk to velopharyngeal function by widening the nasal airway, but velopharyngeal incompetence cannot definitely be attributed to adenoidectomy.