Non-alcoholic fatty liver disease (NAFLD) has become the most common chronic liver disease, along with the prevalence of obesity and metabolic syndrome. Non-alcoholic fatty liver will progress to non-alcoholic steatohepatitis (NASH), NASH-related liver fibrosis and liver cirrhosis, and even hepatocellular carcinoma. Accurate assessment and early intervention are conducive to clinical burden reduction and disease control. Although being the "golden standard" for diagnosing NAFLD, the clinical application of liver biopsy is limited due to well-known limitations and significant complications. Serological testing, as a noninvasive method, has been well-recognized among researchers and clinicians. The understanding of the pros and cons and the application ranges of various methods and indexes is helpful for clinical applications, including providing more diagnosis approaches, improving diagnosis power, relieving pain of patients, and saving medical resources. This article reviews the advances in serological noninvasive diagnostic methods for NAFLD.