The 35-year-old made 48 appearances for the Latics last season as they were relegated to League One.
Warnock, who has two England caps, has also played for Liverpool, Blackburn, Aston Villa, Leeds and Derby.
"We always liked him when he played for Derby and obviously at Wigan most recently," boss Nigel Clough told the club website.
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Burton Albion have signed full-back Stephen Warnock on a one-year deal after he was released by Wigan.