Primary Sjogren's syndrome (pSS) is an autoimmune chronic inflammatory disease with unique clinical presentation and variable outcomes. It affects the exocrine glands including the salivary and lacrimal glands, leading to the sicca syndrome, which is characterized by dryness of the mouth (xerostomia), and eyes (xeropthalmia). Also, extra glandular organ manifestations may develop in some patients. Those patients may later develop devastating symptoms. Initial indicative clinical features and/or diagnostic markers of extra-glandular pSS are under investigated, which delay diagnosis, and management. We used a clustering approach to evaluate and identify clinical manifestations and/or biological markers (features) in Omani patients that may distinguish pSS subtypes. This study was based on data for patients attending the rheumatology clinic at SQUH diagnosed with only pSS (97). Demographic, clinical, and laboratory data were retrospectively collected from the SQUH information system. The studied cohort included 89 females (91.8%) and 8 males (8.1%), i.e., about 9:1 ratio. The average of pSS patients' age at diagnosis is 38.2 years ± (10.4). Compared to other populations, Anti-nuclear and Anti-SSA antibodies are more prevalent (94.9%, 80.60%), while vasculitis and subjective oral sicca are less prevalent (6.1%, 54.5%). To identify the potential pSS clusters, K-means clustering was used. Features which were associated with the best performance were identified. Silhouette and Calinski –Harabasz (CH) scores were used for internal evaluation and for external evaluation, a clinician reviewed the common features between each subtype. Using K means clustering, two clusters showed the best results, and 6 features were identified (i.e., eye and mouth dryness, fatigue, CNS disorders, eye symptoms, and age at diagnosis). The internal evaluation showed satisfactory scores, 0.364, and 55.16, respectively. The identified clinical and biological features that distinguish between the two pSS subtypes may enable early diagnosis of subtypes and facilitate better targeted management.