Dengue fever is becoming one of the major public health problems in the world and its distribution has been premised on the migration of people from infected regions. This study was carried out to determine the prevalence of dengue virus IgGantibody among the patients with febrile conditions attending health facilities in Osogbo metropolis, Southwestern Nigeria. The blood samples collected between July and September, 2014 were tested for Plasmodium falciparum and the sera were subsequently subjected to Enzyme Linked Immunosorbent Assay (ELISA) to detect the dengue virus IgG antibody. Of the hundred consented participants screened, 77% were sero-positive for dengue virus IgG antibody while 41% were positive for P. falciparum. Thirty-three (33%) of the participants were positive for both dengue virus IgG antibody and P. falciparum. No significant difference was found in the prevalence of dengue virus IgG antibody and malaria among the participants (P>0.05). The high prevalence of dengue virus IgG and malaria signifies the need by the government of Osun State to sensitize residents and institute urgent measures to mitigate the resultant effects of morbidity and mortality due to dengue fever and dengue hemorrhagic fever which has hitherto appeared to be alien to the area.