Background: Although ablation therapy has been accepted as a promising and safe technique for treatment of unrespectable hepatic tumors, investigation of its complications has been limited. A physician who performs ablation treatment of hepatic malignancies should be aware of the broad spectrum of complications. Proper management is possible only if the physician Performing ablation understands the broad spectrum of complications encountered after ablation., Objectives: TO SYSTEMATICALLY REVIEW THE COMPLICATIONS AFTER DIFFERENT ABLATION MODALITIES: Radiofrequency ablation (RFA), microwave ablation (MWA) and Nano knife for the treatment of liver tumors and analyze possible risk factors that precipitate these complications., Search Methods: WE PERFORMED ELECTRONIC SEARCHES IN THE FOLLOWING DATABASES: MEDLINE, EMBASE and COCHARNE. Current trials were identified through the Internet (from January 1, 2000 to January 1, 2014). We included only studies who specific mentioned complications after liver ablation therapy (RFA/MWA/Nano knife)., Main Results: A total of 2,588 publications were identified, after detailed examination only 32 publications were included in the review. The included studies involved 15,744 participants. According to the type of technique, 13,044 and 2,700 patients were included for RFA and MWA. Analysis showed a pooled mortality of 0.15% for RFA, and 0.23% for MWA., Conclusions: This systematic review gathers information from controlled clinical trials and observational studies which are vulnerable to different types of bias, never the less RFA and MWA can be considered safe techniques for the treatment of liver tumors.