South Elmham St Mary, known as Homersfield, is a small village and civil parish located on the banks of the River Waveney in Suffolk, UK, on the border with Norfolk. It is one of The Saints.  The village is the home of Homersfield Bridge, a 50-foot span built in 1870 by the Adair estate and the oldest surviving concrete bridge in Britain. It was restored during the 1990s by a partnership between the parish council and various local authorities and heritage bodies.

The village is centred on a small green, around which lie houses from various periods, including a number of traditional thatched houses.  Although the village once had a post office and village shop, only the Black Swan pub now remains, a free house serving Adnams ale and food. There also was once a water mill sited just outside of the village on the road towards St Cross.

This was demolished in the 1930s after the Waveney became too silted up to run the mill. A modern house, built in the approximate style of the previous mill, was built around 1999. Homersfield's old railway station is actually just across the river in Norfolk, the line finally closed in the mid 60's.

Homersfield is bordered by a strip of woodland in which sits the flint-built village church. Behind the woodland is a large lake, the site of a former gravel pit. Although once open as an amenity to the village, it is now a private fishing lake.

Sands and gravels have been quarried at Homersfield since the 1940s. They have yielded bones, teeth and tusks of woolly mammoth, woolly rhinoceros, wild horse, bison and reindeer, dating from colder phases of the Ice Age. A mammoth tusk is on display at the Black Swan inn. A panel explaining the Ice Age wildlife interest is located on the village green.