Archibald Kennedy, 2nd Marquess of Ailsa, KT (25 August 1816 – 20 March 1870) was a Scottish peer and soldier.
Born at Dunottar, he was the eldest son of Archibald Kennedy, Earl of Cassilis, himself the oldest son of Archibald Kennedy, 1st Marquess of Ailsa, and his wife Eleanor, daughter of Alexander Allardyce. His father having predeceased him in 1832, Kennedy succeeded to his grandfather's titles in 1846. Eleanor as Marchioness was involved with Catharine Tait's Ladies Diocesan Association visiting the poor in the City Road Workhouse.
Kennedy served in the British Army as a lieutenant in the 17th Lancers (Duke of Cambridge's Own). Having been previously a Deputy Lieutenant, he was appointed Lord Lieutenant of Ayrshire in 1861, an office he held until his death nine years later.