Aim. To determine the prevalence of HIV infection among patients seen at the surgical oncology unit of Donka (Conakry, Guinea). Method. We conducted a retrospective and descriptive study of HIV infection in cancer patients from May 2007 to December 2012. Social characteristics (age, gender, marital status, and education) and immune status (HIV type, CD4 count) were reviewed. Results. Out of 2598 cancer patients, 54 (2.1%) tested positive for HIV. There were 11 (20.4%) defining AIDS and 43 (79.6%) nondefining AIDS cancers. The most frequent cancers were breast (14) (26.0%), non-Hodgkin lymphoma (6) (11.1%), liver (6) (11.1%), eye and annexes (6) (11.1%), and cervical cancer (5) (9.3%). These patients were female in 34 (63.0%) and had a median age of 39 years and body mass index was 20,3Kg/m(2). They were unschooled in 40 (74.1%) and married in 35 (64.8%). CD4 count showed a median of 317cells/mL. Antiretroviral treatment was performed in 40 (74.1%). Conclusion. HIV prevalence is higher in patients in our unit of surgical oncology. Breast cancer was the most common in this association. A national survey of a large sample is needed to determine the true prevalence and impact of HIV on cancer prognosis.