Dengue fever is a major infection in the world which geographically expanded. The disease is caused by dengue virus that transfers by Aedes mosquito mainly Ae. aegypti. It is endemic in Saudi Arabia and several outbreaks were reported. The virus primary affects different age groups. Dengue virus can cause classic dengue fever, dengue hemorrhagic fever and dengue shock syndrome. This study reviewed the clinical pictures, laboratory results and outcome of DF in adults and pediatrics. The retrospective descriptive study included 274 DF patients was conducted at Andalusia Hospital, Jeddah, Saudi Arabia over one year. Demographic data, clinical spectrum and laboratory investigations were recorded. The results showed that pediatrics were 45/274 (16.4%), while adults were 229 (83.6%), males were more dominant than females (30 or 66.7% & 169 or 73.8%) in pediatrics and adults respectively. Headache myalgia, and retro-orbital pain were the main clinical pictures in adults (p<0.05), while vomiting and diarrhea were prevalent in pediatrics (p<0.05). Anemia,
thrombocytopenia and elevated liver enzymes were significantly higher in adults than pediatrics (p<0.05). Hospital stay and severe DF (DHF & DSS) were significantly higher in adults than pediatrics (p<0.05).