Morwenstow is a civil parish in north Cornwall, England. The parish is near the coast, about six miles (10 km) north of Bude and within the Cornwall Area of Outstanding Natural Beauty (AONB).
Morwenstow is the most northerly parish in Cornwall. As well as the churchtown (a hamlet called Crosstown), other settlements in the parish include Shop, Woodford, Gooseham, Eastcott, Woolley and West Youlstone. The population at the 2011 census was 837. Morwenstow parish is bounded to the north and east by parishes in Devon, to the south by Kilkhampton parish and to the west by the Atlantic. The River Tamar has its source at a spring on Woolley Moor, at , which is in the parish near the border with Devon.
Morwenstow is the one-time home of the eccentric vicar and poet Robert Stephen Hawker (1803–1875), the writer of Cornwall's anthem Trelawny. Hawker is also credited with reviving the custom of Harvest Festivals.