Objectives: Primary ciliary dyskinesia (PCD) is a disorder affecting the structure and function of motile cilia. Transmission electron microscopy is one method that can be used to examine ciliary ultrastructure in airway biopsies. Although the role of ultrastructural findings in PCD has been described in the literature, this role has not been well studied in the Middle East or, by extension, Oman. This study aims to describe ultrastructural features in Omani patients with high suspicion of PCD. Methods: This retrospective cross-sectional study included 129 adequate airway biopsies obtained between 2010–2020 from Omani patients suspected of having PCD. Results: Ciliary ultrastructural abnormalities in our study population were outer dynein arm associated with inner dynein arm defects (8%), microtubular disorganisation associated with inner dynein arm defect (5%), and isolated outer dynein arm defect (2%). Most of the biopsies sowed normal ultrastructure (82%). Conclusion: In Omani patients suspected to have PCD, normal ultrastructure was the commonest feature. Keywords: Cilia; Primary Ciliary Dyskinesia; Airway Biopsy; Transmission Electron Microscopy; Ultrastructure; Oman.