The River Lemon is a 16-kilometre (9.9 mi) river in the county of Devon in southwest England. It is a tributary of the River Teign, starting on Dartmoor by Haytor, and ending in Lyme Bay. It rises on the south-east side of Dartmoor near Haytor, joins with the River Sig and the Langworthy Brook at Sigford, then passes the village of Bickington. Lower down, it is joined by the Kestor Brook and it then flows through the woods in Bradley Valley, past the manor house of Bradley, and through the town of Newton Abbot where it flows through a 400-metre-long tunnel below the town centre. Just below the town, the river joins the River Teign at , near the head of its estuary.