Adenoviruses are responsible for a broad spectrum of diseases, including upper and lower respiratory tract infections (URTIs and LRTIs, respectively), conjunctivitis, gastroenteritis, and hemorrhagic cystitis. The aim of this study was to determine the adenovirus (AdV) types isolated from clinical specimens by polymerase chain reaction (PCR) and DNA sequencing methods. A total of 22 AdV strains isolated between January 1st 2011 to May 31th 2011, from various samples (295 nasopharyngeal swabs, 42 conjunctival swabs, 13 stool) sent to our routine virology laboratory were included in the study. Of the 22 patients whose samples yielded adenovirus positivity, 8 were adult (4 were male; median age: 32.5 years) and 14 (7 were male; median age: 1 year) were children. Those specimens (14 nasopharyngeal swabs, 7 conjunctival swabs, 1 stool) were obtained from patients with URTIs (n= 6), LRTIs (n= 8), conjunctivitis (n= 7) and gastroenteritis (n= 1). For the isolation and identification of adenoviruses, rapid (shell vial) cell culture and direct immunofluorescence antibody methods were used, respectively. Molecular typing of adenoviruses were performed by PCR and sequencing of a partial region (hipervariable region 1-6) of the hexon gene. PCR primers (Adhex F1, Adhex R1) used for DNA amplification were from those described by Lu and Erdman, previously. If insufficient DNA was amplified from the first reaction for sequencing, a nested PCR was performed using Adhex F2 and Adhex R2 primers. Sequencing was performed using the amplification primers and Sequence Reagent Mix-DYEnamic ET Terminator Cycle Sequencing Kit (Amersham Pharmacia Biotech Inc, USA) on ABI PRISM 310 Genetic Analyzer (Applied Biosystems, USA). Obtained adenovirus sequences were typed by BLAST analysis and three AdV types namely type 3, 4, and 8 were identified. In our study, AdV type 3 was detected in a gastroenteritis case and six cases with URTIs and LRTIs (n= 7, 31.8%). AdV type 8 was identified as the cause of conjunctivitis in seven patients and of URTIs and LRTIs in five patients (n= 12, 54.5%). AdV type 4 was found to be associated with URTI in one, and LRTIs in two patients (n= 3; 13.7%). Our data indicated that AdV type 8 was the most prevalent type in patients with conjunctivitis and URTIs, while AdV type 3 was the most prevalent type in patients with LRTI. BLAST analysis was thought to be useful for the molecular typing of adenoviruses. In conclusion, advanced studies with large number of specimens are necessary to achive a reliable, detailed national adenovirus database.