Coloured rice is rich in polyphenols and has been shown to have significant antioxidant and anti-adipogenic potential. The study aimed to investigate the anti-adipogenic properties of polyphenol extract (PE) derived from Australian-grown rice varieties. Eight wholegrain pigmented rice varieties were screened for their polyphenol content and antioxidant activity, of which, Yunlu29 (red), Purple (purple) and Reiziq (brown) had the highest values. The selected varieties were then subjected to in-vitro investigation to determine the effect of rice-derived PE on adipocyte differentiation. Lipid accumulation and peroxisome proliferator-activated receptor gamma (PPARγ) expression were quantified by oil red O staining and RT-PCR respectively. PE from Yunlu29 (red) and Purple rice varieties significantly reduced (p < 0.001) lipid accumulation by 53% and 56% respectively and PPARγ expression in adipocytes by 61.2% and 35.6% respectively. PE from Reiziq (brown), did not inhibit lipid accumulation in adipocytes however, did reduce PPARγ expression (p < 0.001).