HER-2 is overexpressed in 25% of breast cancers and provides a poor prognostic factor, affecting treatment decisions including administration of trastuzumab. Single reports show a lack of HER-2 in non-Hodgkin lymphomas (NHLs) using immunohistochemical (IHC) test. The present study evaluates HER-2 in NHLs using the chromogenic in situ hybridisation (CISH) test, which is more accurate than IHC, to seek new prognostic factors. The secondary aim of the study is to investigate efficacy of using trastuzumab in the treatment of NHLs in future studies. Fifty eight formalin-fixed, paraffin-embedded tissue specimens presenting various NHLs were examined using CISH test. Sixty six percent of all patients were diagnosed at stages III and IV. Histologically, 30 (52%) were low grade and 28 (48%) were intermediate and high grade. HER-2 was negative in all NHLs. Because there is no HER-2 gene amplification in NHL, HER-2 cannot be used as a prognostic factor and should not play a role in biological targeting therapy in non-Hodgkin lymphoma.