ObjectiveTo observe the effect of gastrodin on the steroid regulatory element-binding protein 1c （SREBP1c） signaling pathway in high-fat high-cholesterol diet （HFHC）-induced mice and explore the mechanism of gastrodin in the treatment of non-alcoholic fatty liver disease （NAFLD）. MethodEight-week-old male C57BL/6J mice were used in vivo and divided into the following four groups， with six mice in each group： normal group， gastrodin group （50 mg·kg-1）， model group， and model + gastrodin group （50 mg·kg-1）. NAFLD model was established by feeding mice with HFHC for four weeks， and the mice were euthanized and the liver tissues were collected after four weeks. In vitro experiments were performed using Huh7 cells which were divided into five groups， and induced with free fatty acids （FFA， 200 μmol·L-1， oleic acid-palmitic acid 2∶1） to establish an NAFLD cell model. After 24 h， different concentrations of gastrodin （0， 5， 10， 20， and 40 μmol·L-1） were added to each group and cultured for another 24 h. Oil red O staining was used to detect lipid accumulation in mouse liver and Huh7 cells. Hematoxylin-eosin （HE） staining was used to observe pathological changes in liver tissue. Levels of serum total cholesterol （TC）， low-density lipoprotein cholesterol （LDL-C）， and triglycerides （TG） were measured using an automatic biochemical analyzer. Relevant assay kits were used to detect liver TC， TG， and FFA levels. Real-time quantitative polymerase chain reaction （Real-time PCR） and Western blot were used to detect the expression of lipid synthesis-related proteins fatty acid synthase （FASN）， acetyl-CoA carboxylase 1 （ACC1）， and stearoyl-CoA desaturase 1 （SCD1）. ResultCompared with the normal group， the model group showed significantly increased serum TC， LDL-C， and TG levels （P<0.01）， liver TC， TG， and FFA levels （P<0.01）， increased lipid accumulation in Huh7 cells （P<0.01）， and significantly increased expression levels of lipid synthesis-related genes SREBP1c， FASN， ACC1， and SCD1 in mice and Huh7 cells （P<0.01）. Compared with the model group， after gastrodin treatment， the serum TC， LDL-C， and TG levels in mice significantly decreased （P<0.05， P<0.01）， the severity of fatty liver disease improved significantly， liver TC， TG， and FFA levels decreased significantly （P<0.05， P<0.01）， lipid accumulation in Huh7 cells decreased significantly （P<0.05， P<0.01）， the expression levels of lipid synthesis-related genes SREBP1c， FASN， ACC1， and SCD1 in mice and Huh7 cells decreased significantly （P<0.05， P<0.01）. ConclusionGastrodin can reduce hepatic lipid accumulation and blood lipid levels， improve HFHC-induced NAFLD， and its mechanism of action may be related to the regulation of the SREBP1c lipid synthesis-related signaling pathway.