Jansenville is a town in Sarah Baartman District Municipality in the Eastern Cape province of South Africa.
Town on the Sundays River, 87km south of Graaff-Reinet. Laid out on the farm Vergenoegd in 1854, it was proclaimed in 1855 and became a municipality in 1881. Said to have been named after General Jan Willem Janssens (1762-1838), the last Batavian Governor of the Cape.