Summary: High percentage of liver tumours are not suitable for surgica! resection and there are no other effective treatment modalities for these tumours. Therefore there is need to develop some new therapeutic strategies. Currently methods of gene therapy are extensively explored. One of those represents replication competent oncolytic viruses that are engineered for selective tumour destruction. Genetically modified adenoviruses and herpesviruses are entering the first clinical trials as therapeutics tools for liver tumours. The preclinical and first preliminary clinical results hold promise for the treatment of cancer. The aim of this review is to describe current possibilities of oncolytic viruses in the treatment of liver tumours.