Dengue is the fastest emerging arboviral infection and became a major public health concern in tropical and subtropical countries. Dengue infections can result in a wide spectrum of disease severities ranging between dengue fever (DF) to the life-threatening dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). This study was performed to find out the varied presentations and laboratory findings to put forward an overview about dengue syndrome in Bangladesh, in order to create better awareness and diagnostic skills among the health care providers. This hospital based observational study was conducted in the department of Medicine, Square Hospitals Ltd. during January, 2008 to December, 2010. A total of 262 adult subjects of both sexes having dengue syndrome were included in this study. Dengue syndrome was common in younger age group and the majority (72%) was below 45 years of age. All the patients had fever and the majority had malaise (96%), severe headache (72%) and musculoskeletal pain (65%). Skin rash (47%) was the commonest hemorrhagic manifestation while tourniquet test (49%) and low pulse pressure (37%) were the commonest clinical signs. All had thrombocytopenia (100%) and the majority had leukopenia (84%) and elevated liver transaminase (ALT-74%, AST-88%). Most of the subjects developed anti dengue antibody (IgM-92%, IgG -72%). All subjects survived.