Background: The global prevalence of dengue has increased dramatically in recent decades, with currently 50 million clinical cases and up to 5 million hospitalisations annually. Caused by one of five closely related but antigenically distinct virus serotypes (DEN-1 to DEN-5), dengue is an emerging mosquito-borne viral disease and an important public health problem in Nepal. Objectives: This study was designed to determine the occurrence of dengue in clinically suspected patient in Narayani Zone, Central Nepal. Methods: A descriptive cross-sectional study was conducted between January 2010 and December 2011 at Chitwan Medical College Teaching Hospital, Bharatpur, the fifth largest city of Nepal. A total of 590 blood samples were collected and processed for anti-dengue immunoglobulin (Ig)M by antibody isotype-capture enzyme-linked immunosorbent assay. Results: Positive detection of anti-dengue IgM was found in 8.5% of patients (50/590 cases). The highest number of dengue cases was observed in the 21-30 years age group with greater predilection in males than in females. The positive cases showed higher frequency in winter season than at other times of year. There was a significantly greater prevalence of dengue among residents of urban locations compared to those from rural areas. Conclusions: A high percentage of dengue positivity among suspected patients demands early investigation and careful management to prevent significant outbreaks of dengue fever and dengue haemorrhagic fever.