Background: Dengue fever is a viral disease which is transmitted by Aedes mosquitoes. It has becomea significant public health concern in Bangladesh. The clinical symptoms of dengue fever are often selflimiting.But severe cases can lead to different types of complications especially cardiac complications.Troponin-I is a cardiac biomarker which is elevated in myocardial injury. Its association with denguevirus infection, particularly the dengue patients who are NS1 antigen positive, remains understudied.Objective: This objective of this study is to find out the association of Troponin-I level with dengueinfection in adult NS1 positive dengue patients in a tertiary care hospital in Bangladesh. Methods: Across-sectional study was conducted on adult patients diagnosed with dengue fever and confirmed bypositive dengue NS1 antigen at a tertiary care hospital. The levels of Troponin-I were measured andcorrelated with clinical symptoms, duration of disease, and other relevant laboratory findings. Dataanalysis included statistical methods to evaluate the significance of Troponin-I as a marker for cardiacinvolvement in dengue. Results: The study examined the demographic data, clinical characteristics, andlaboratory findings of 52 participants, divided into Troponin-I positive (n=16) and Troponin-I negative(n=36) groups. Significant differences were observed in gender distribution and socioeconomic status.Troponin-I positivity was most prevalent among older individuals (>46 years, p < 0.001). Clinicalparameters showed strong associations with symptoms such as chest pain, headache, and vomiting(p < 0.001). Additionally, laboratory analysis identified significant variations in hemoglobin, RBCcount, serum bilirubin, SGPT, and creatinine levels (p < 0.05). These findings highlight key clinicaland laboratory distinctions between Troponin-I positive and negative groups, offering valuable insightsinto their diagnostic and prognostic significance. Conclusion: This study shows distinct demographic,clinical, and laboratory patterns among patients of dengue fever with positive dengue NS1 and positiveTroponin-I. Troponin-I positivity in dengue patients is significantly associated with older age, clinicalsymptoms and laboratory abnormalities, while dengue NS1 positive younger individuals with negativeTroponin-I were found to developed milder symptoms. Gender differences and symptoms variabilityunderscore the need for tailored, age-specific diagnostic and therapeutic strategies.