objective: The objective of this study was to evaluate the probable mechanism of action of Biochanin A (BCA) on high-fat diet-induced insulin resistance mice. methods: Twenty-four male C57/BL/6J mice were divided into two and fed either control diet or a high fat-high diet (HFD). After 6?weeks, mice were grouped into: Control, Control?+?BCA, HFD and HFD?+?BCA (?=?6). Mice were made diabetic by feeding them an HFD. results: Body weight, plasma glucose, insulin, leptin levels and HOMA values were significantly lower in the BCA supplemented HFD group when related to the HFD group. Furthermore, BCA supplementation significantly increased Insulin receptor substrate 1 (IRS 1), PI3K, Akt and Glucose transporter type 4 (GLUT-4) protein abundance in skeletal muscle when equated with HFD. conclusions: This study demonstrates that BCA can improve insulin sensitivity by activating insulin signalling, suggesting that it may possess antidiabetic activities.