Introduction: Before the Coronavirus Disease 2019 (COVID-19) arrival and its pandemic, dengue was already a significant cause of epidemics in South East Asia and Latin America. In 2020 with their cocirculation, coinfections began to be observed and reported in different countries. As expected, this syndemic is evident in different areas and deserves proper characterisation and studies in Peru. Methods: We retrospectively assessed the clinical, epidemiological, diagnostic characteristics and outcomes in a Social Security Hospital of Chiclayo, Lambayeque, Peru, of patients that were diagnosed simultaneously with COVID-19 and dengue during May–August 2020. Results: A total of 50 patients with COVID-19/dengue coinfection were identified. Of them, 60% presented thrombocytopenia, and 52% fever, among other findings. The case fatality rate in this group was 28%, being higher in those patients initially classified as severe dengue (100%), as well as in females (55%) than males (21%) (OR = 4.65; 95%CI 1.18–18.45). Discussion: Co-occurrence of COVID-19/Dengue is growing as a consequence of the syndemic of these viral diseases in endemic areas, such as Latin America, and as both conditions may evolve to severe disease, their epidemiological but clinical interaction in terms of outcomes need further assessment in future studies in the region.