In a retrospective study including 336 patients with NHL changes of several hematological and biochemical parameters, which are usually determined in the basic diagnostic of these diseases were examined and correlated to grade of malignancy, stage, organ involvement and presence of B-symptoms. At the time of diagnosis, the most frequent changes were elevation of ESR, LDH and alpha-2-globulins in the serumprotein electrophoresis. The latter two were significantly correlated to the grade of malignancy. Regarding the stage of disease, elevated LDH, anemia and thrombopenia were linked to an advanced disease, anemia and thrombopenia because of a correlation to the infiltration of bone marrow. Elevation of alkaline phosphatase was a significant sign of liver involvement. All parameters with the exception of hematological findings were more frequent changed in patients with clinical B-symptoms then in patients without these symptoms. At the time of relapse, no specific changes were observed in relation to the previous complete remission with exception of an elevation of the LDH, which was found in 60% of relapses in high grade malignant lymphomas.