Persistence is dormant phenotypic variants of regular cells that are tolerant to antibiotics. The persistent cells did not acquire antibiotic resistance genetically, being produced in response to antibiotic stress. Because of dormant phenotypic variants due to little or no cell-wall synthesis, translation, or topoisomerase activity, persistent cells show antibiotic tolerance. Recently, such persistent cells have been reported in many bacterial pathogens and are known to play significant roles in clinical settings, particularly in chronic diseases such as cystic fibrosis. Therefore, development of anti-persister drug and appropriate antibiotic treatment are required to eliminate the persisters and to prevent the development of antibiotic resistance. Screening of genes related to persister formation would lead to new drugs to combat persisters during infection. By reviewing recent publications, we summarize phenomenon of survival and tolerance in persistent cells.