Background: Adenovirus is the primary etiological agent of Epidemic Keratoconjunctivitis (EKC) globally. Conjunctivitis constitutes a significant proportion of consultations in ophthalmology clinics and exerts a substantial financial strain on the healthcare system. Consequently, 1% of all medical consultations in the United States pertain to conjunctivitis.Aim: to evaluate the prevalence of Adenovirus serotypes in epidemic keratoconjunctivitis patients and its clinical manifestation.Materials and methods: This cross-sectional and descriptive study utilized a simple sampling method to enroll 115 eligible patients, aged 4 to 17 years, who were referred to the ophthalmology emergency department of Azadi Teaching Hospital from March 1, 2024, to December 10, 2024. Sixty individuals of the same age as the research patients, devoid of diabetes or any other chronic illnesses, constituted the control group. Four milliliters of blood were extracted from patients via vein puncture into Vacutainer tubes, and the sera were subsequently frozen at -20 degrees Celsius for future serological analysis utilizing the enzyme-linked immunosorbent assay (ELISA) method to detect specific viral IgM antibodies. Results: The study indicated that 21.74% of patients with conjunctivitis possess adenovirus IgM antibodies, in contrast to 3.33% of the control group.The study indicated that 60% of patients infected with adenovirus were in urban areas, whereas 40% were from rural areas. The largest incidence of adenovirus infection (56%) occurred in kids aged 4-6 years, followed by 24% in the 7-12 year age group.  The study indicated that 11 patients (44%) with ocular adenoviral infection exhibited flu-like symptoms prior to or concurrent with their ocular issues, whereas 14 patients (56%) with ocular adenoviral infection did not present any systemic manifestations.  The majority of patients with keratoconjunctivitis and adenovirus infection had itching, redness, grittiness, tearing, and clear mucinous discharge.Conclusions: A significant association was observed between adenovirus infection and conjunctival injection in patients with EKC. This study emphasizes the need for accurate viral diagnostics to guide effective management and reduce unnecessary antibiotic use.