Belshaw is a Site of Special Scientific Interest (SSSI) in Lincolnshire, England. It lies to the west of the village of Belton in the Isle of Axholme. The site, which was designated a SSSI in 1988, is a short length of land along a disused railway line and is important because it supports a colony of greater yellow-rattle. This is a nationally rare plant which receives special protection under Schedule 8 of the Wildlife and Countryside Act, 1981. Once widely distributed, this species is now known to occur at only six localities in Great Britain.