Nonalcoholic fatty liver disease （NAFLD） is one of themajor causes of chronic liver injury. NAFLD includes awide range of clinical conditions from simple steatosisto nonalcoholic steatohepatitis （NASH）, advancedfibrosis, and liver cirrhosis. The histological findingsof NASH indicate hepatic steatosis and inflammationwith characteristic hepatocyte injury （e.g. , ballooningdegeneration）, as is observed in the patients withalcoholic liver disease. NASH is considered to be apotentially health-threatening disease that can progressto cirrhosis. A liver biopsy remains the most reliablediagnostic method to appropriately diagnose NASH,evaluate the severity of liver fibrosis, and determinethe prognosis and optimal treatment. However, thisinvasive technique is associated with several limitationsin routine use, and a number of biomarkers havebeen developed in order to predict the degree of liverfibrosis. In the present article, we review the currentstatus of noninvasive biomarkers available to estimateliver fibrosis in the patients with NASH. We also discussour recent findings on the use of the glycated albuminto-glycated hemoglobin ratio, which is a new index thatcorrelates to various chronic liver diseases, includingNASH.