Southdean is a hamlet in the Scottish Borders area of Scotland, on the A6088, by the Jed Water and in the Wauchope Forest area. Other settlements nearby include Abbotrule, Bedrule, Bonchester Bridge, Denholm, Hallrule, Hobkirk and the Swinnie Forest.

Southdean Scots: Soothdean
A6088 road through Southdean
Southdean Location within the Scottish Borders
Language	English Southern Scots
OS grid reference	NT631092
Council area	Scottish Borders
Lieutenancy area	Roxburgh, Ettrick and Lauderdale
Country	Scotland
Sovereign state	United Kingdom
Post town	HAWICK
Postcode district	TD9
Dialling code	01450
Police	Scotland
Fire	Scottish
Ambulance	Scottish
UK Parliament	Berwickshire, Roxburgh and Selkirk
Scottish Parliament	Ettrick, Roxburgh and Berwickshire
List of places UK Scotland 55°22′34″N 2°35′01″W / 55.3761°N 2.5835°W / 55.3761; -2.5835

Ruins which can be seen nearby include the remains of Southdean Old Parish Church, the remains of Dykeraw Tower, and the remains of Slack's Tower.

James Telfer (1802 - 1862) was born in Southdean, and wrote ballads about farming life, typically with a zoological slant.