Human immunodeficiency virus (HIV) causes AIDS which is still a global public health threat. Current drugs against HIV infection cannot eradicate the virus therefore, research on new drug targets continues. HIV capsid protein, which has a highly conserved sequence and is sensitive to mutations, has critical roles in the virus lifecycle, making it a high-potential drug target. A nanobody is the antigen-binding domain of heavy-chain only antibodies of camelids. Small size, thermal stability and ease of production makes nanobodies ideal antibody fragments for therapeutic and diagnostic purposes. In the literature, a nanobody binding to the HIV-1 capsid-N terminal domain (NTD) has been reported. The aim of this thesis is to examine the potential of this nanobody as a biotechnological drug candidate against the HIV-1 and HIV-2 capsid proteins. In the study, HIV-1 capsid was expressed, purified and biophysically characterized. Thermal and chemical denaturation of the protein were done, the melting temperature and unfolding free-energy values of the protein were determined. In-vitro oligomerization of the HIV-1 capsid was performed and observed that the protein self-oligomerized over time. Pure HIV-2 capsid protein could not be produced recombinantly. Thereupon, HIV1 capsid-NTD and HIV-2 capsid-NTD proteins were expressed and purified. Secondary structure of HIV-1 capsid, HIV-1 capsid-NTD and nanobody were analyzed with circular dichroism (CD) spectroscopy and the results matched with the literature. Isothermal titration calorimetry (ITC) experiments were done to examine the HIV-1 capsidnanobody interaction, but good binding was not observed between the two proteins. Future work requires repeating ITC experiments.