Chard (Beta vulgaris L. var cicla) is one of the medicinal herbs used by diabetics in Turkey. It has been reported to reduce blood glucose. We have investigated the effect of chard extracts on the liver by biochemical and morphological investigation. The plant extract was administered by the gavage technique to rats at a dose of 2 g/kg every d for 28 d, 14 d after experimental animals were made diabetic. In the diabetic group, some degenerative changes were observed by light and electron microscope examination, but degenerative changes decreased or were not observed in the diabetic group given chard. In the diabetic group, blood glucose levels, serum alanine, aspartate transaminase, alkaline phosphatase activities, total lipids, sialic and uric acid levels, liver lipid peroxidation (LPO), and nonenzymatic glycosylation (NEG) levels increased, while blood glutathione, body weight, and liver glutathione (GSH) levels decreased. The diabetic group given chard, serum alanine, aspartate transaminase, alkaline phosphatase activities, total lipid level, sialic and uric acid levels, blood glucose levels, and liver LPO and NEG levels decreased, but the other values increased. As a result of all the morphological and biochemical findings obtained, it was concluded that the extract of this plant has a protective effect on the liver in diabetes mellitus.