Emily FitzGerald, Duchess of Leinster, known before 1747 as Lady Emily Lennox, from 1747 to 1761 as The Countess of Kildare and from 1761 to 1766 as The Marchioness of Kildare, was the second of the famous Lennox sisters, daughters of Charles Lennox, 2nd Duke of Richmond.

The Lennox sisters were four eighteenth-century British aristocrats, the daughters of Charles Lennox, 2nd Duke of Richmond (1701–1750) by his wife Lady Sarah Cadogan (1705–1751).