Background: Nasopharyngeal stenosis (NPS) is a rare condition defined as the obstruction of the communication between the oropharynx and nasopharynx owing to scar contracture of the soft palate, tonsillar pillars, and posterior pharyngeal wall. NPS could be primary (attributed to a disease process such as rhinoscleroma) or secondary caused by prior surgery. In this study, we discuss the clinical manifestation of the acquired nasopharyngeal stenosis (NPS) and to investigate if there is a relation between the grade of the acquired NPS and the severity of obstructive sleep apnea (OSA) and patients’ symptoms. So, this cross-sectional study was conducted on patients who had post-surgical NPS of different grades. Then, the severity of snoring ± OSA and VAS of symptoms in those patients was assessed in different grades of the NPS, and the results were also statistically compared. Results: Within the included 22 patients, there were no statistical differences between grade 1 and in grade 2 as regards age (p = 0.0619) or sex (p = 0.21137). The mean AHI was significantly more (p = 0.004) in grade 2 NPS than grade 1 NPS. The VAS of difficult nasal breathing and dysphagia were significantly worse (p < 0.0001) in grade 2 NPS than in grade 1, while the VAS of snoring did not differ significantly (p = 0.3466) between grade 1 and grade 2 NPS. Conclusion: Grade 2 NPS leads to significantly more severe AHI, dysphagia, and difficult nasal breathing than grade 1 NPS. But the difference in the grade of NPS did not cause differences in the snoring intensity.