Abstract: This study assessed the level of awareness and knowledge of HIV Counselling and Testing (HCT) among adults of reproductive age in Osun State with the aim of providing a background for a study on HCT uptake. Three Local Government Areas (LGAs), namely Atakumosa West, Olorunda and Ayedaade were randomly selected for the study which employed both quantitative and qualitative methodologies. The quantitative survey employed an analytical cross-sectional design using an interviewer-administered, semi-structured questionnaire to elicit information from 720 male and female respondents of reproductive age group. The qualitative aspect consisted of twelve Focus Group Discussions in all, four conducted in each of the LGAs. The data were analysed using descriptive and inferential statistics and the results of both the qualitative and quantitative methods were triangulated. The results showed that 84.0% of the respondents were aware of HCT. Thirty seven percent had correct understanding, 88.4% knew where it could be accessed while 89.6% knew that HCT was beneficial. The knowledge of HIV status and access to early treatment were the most important benefits reported. Sixty-one percent of the respondents had fair knowledge of HCT. The study concluded that adults of reproductive age in Osun State had fair knowledge of HCT.