The frequency of EBV demonstrated in patients with Hodgkin's lymphoma (HL) shows geographical variability. In the present study, we investigated the frequency of EBV in HL patients in the Czech Republic. The presence of EBV was determined by immunohistochemistry (IHC) with anti LMP-1 antibody and by in situ hybridization (ISH) method for EBERs. We studied 142 cases with HL. The age of patients ranged from 4 to 82 years. The male to female ratio was 1.2 (males 55.6%). In the series of 142 patients 47 (33%) positive cases were found. The incidence of EBV-positive results was significantly, higher in males than in females (70.2 vs. 29.7%, p = 0.023). Five patients were found in the age group below 10 years. They were positive with LMP-1 antibody and for EBERs in ISH method. The same results were discovered in two patients above the age of eighty. The most frequent histologic types of HL were nodular sclerosis (64 cases) and mixed cellularity (62 cases), respectively. The former type contained 16 EBV-positive cases (25%) and the latter 24 (38%) positive cases. The lymphocyte depletion type 2 (67%); lymphocyte rich type 5 (38%). EBV-positivity examined by ISH and IHC methods determined not only diagnostic Hodgkin cells and Reed-Sternberg cells but also small lymphocytes. In IHC method were small lymphocytes positive in 11 cases, more sensitive ISH revealed 32 positive cases.