Loddon was an electoral district of the Legislative Assembly in the Australian state of Victoria from 1856 to 1859. It was based in northern Victoria around the Loddon River. Its area was defined in the Victoria Constitution Act of 1855 as: "Bounded on the West by the River Avoca, from its Source in the great dividing Range to its Entrance to Lake Bael Bael, thence by a Line Northward to the River Murray ; on the North by the River Murray ; on the East by the River Campaspe to its Junction with the Coliban, and on the South by the Northern Boundary of the Counties of Dalhousie and Talbot to the commencing Point, excepting the Country comprised in the Electoral Districts of the Castlemaine Boroughs and of the Sandhurst Boroughs."