Background. Kaposi sarcoma (KS) may arise as a complication of kidney transplantation. In the Saint Luc Teaching Hospital in Brussels, patients of both Belgian and foreign origin are treated. The prevalence of human herpes virus 8 (HHV‐8) infection differs in different geographical settings. We wanted to estimate the background infection rate and the risk of infection in our transplant population: a first step towards evaluating the necessity of HHV‐8 screening. Methods. Serum samples were taken from 210 organ donors over a period of 7 years (30 per year) and from 200 kidney recipients from whom two sera were tested, one pre‐transplant and the second 6–12 months post‐transplant. All sera were screened for HHV‐8 by an enzyme‐linked immunosorbant assay using recombinant ORF 65 and ORF 73 antigens and an immunofluorescence assay for the latent antigen. Reactive samples were confirmed by western blotting. Results. Seven donors (3.3%) were positive for HHV‐8 antibodies. Of 198 pre‐transplant sera available for evaluation, 15 were positive (7.6%). Post‐transplantation 18/199 (9%) were positive: four (2.1% of negatives) had a documented seroconversion and one lost the antibodies. No patients developed KS. Conclusions. A substantial number of kidney transplant patients already had antibodies to HHV‐8 at the time of transplantation. A further 2.1% of seronegative patients had seroconversion, which could have been acquired through the transplanted organ (3.3% of donors were positive) or through transfusion.