Martham Broad is a 60-hectare (150-acre) national nature reserve north of Great Yarmouth in Norfolk.

It is managed by the Norfolk Wildlife Trust,[1][2] and is part of the Upper Thurne Broads and Marshes Site of Special Scientific Interest.

[3] It is also part of the Broadland Ramsar site[4] and Special Protection Area,[5] and The Broads Special Area of Conservation.

[6] This reserve is composed of two shallow broads divided by the River Thurne, together with fen, reedbeds and marshes.

There are a number of bat species and breeding birds include bearded tits, common terns, Cetti's warblers and marsh harriers.