Seeds of Apium graveolens L. (Apiaceae) and Hygrophila auriculata (K. Schum.) Heine (Syn. Astercantha auriculata Nees, Acanthaceae) are used in Indian systems of medicine for the treatment of liver ailments. The antihepatotoxic effect of methanolic extracts of the seeds of these two plants was studied on rat liver damage induced by a single dose of paracetamol (3 g/kg p.o.) or thioacetamide (100 mg/kg, s.c.) by monitoring several liver function tests, viz. serum transaminases (SGOT and SGPT), alkaline phosphatase, sorbitol dehydrogenase, glutamate dehydrogenase and bilirubin in serum. Furthermore, hepatic tissues were processed for assay of triglycerides and histopathological alterations simultaneously. A significant hepatoprotective activity of the methanolic extract of the seeds of both the plants was reported.