Clarence Threepwood, 9th Earl of Emsworth, Viscount Bosham is a fictional character created by British comic writer P. G. Wodehouse. Lord Emsworth, the benevolent though somewhat absent-minded patriarch of the large Threepwood family, lives at Blandings Castle, where he longs for peace and quiet, but must face the unpleasant reality of his domineering sisters and familial duties. His household forms the setting for a number of Wodehouse's books.

Lord Emsworth's favorite pastime is his garden, and he is always a competitor and often a winner in Shropshire's Agriculture Show. At first he contents himself with entering large pumpkins, most notably one named Blandings Hope, but later he enters his prize sow, the Empress of Blandings. The Empress's primary competitor is the Queen of Matchingham, who belongs to Sir Gregory Parsloe-Parsloe, Emsworth's neighbor.

Lord Emsworth has nine sisters, two brothers, two sons, at least one daughter, and many in-laws; for a full list of his family members, see the list of P. G. Wodehouse characters.