William Barclay

• William Barclay (jurist), Scottish jurist
• William Barclay (writer), Scottish writer
• William Barclay (painter), English miniature painter
• William Barclay (Northern [Ireland politician)], Northern Irish Senator
• William Barclay (theologian), theologian and writer of Bible commentaries
• William A. Barclay, New York State Assemblyman
• William [Edward Barclay], football manager of Everton and of Liverpool
• Bill Barclay, American athlete and coach