Willem de Keyser may refer to:

• Willem de Keyser (architect) (1603–after 1674), Dutch architect and sculptor
• Willem de Keyser (painter) (c. 1647–1692), Flemish painter

• Canoeing at the 1972 Summer Olympics – Men's slalom C-2
• Canoeing at the 1972 Summer Olympics – Men's slalom K-1
• Canoeing at the 1972 Summer Olympics – Women's K-1 500 metres
• Canoeing at the 1972 Summer Olympics – Women's K-2 500 metres
• Canoeing at the 1972 Summer Olympics – Women's slalom K-1
• Canoeing at the 1976 Summer Olympics - Men's C-1 1000 metres
• Canoeing at the 1976 Summer Olympics - Men's C-1 500 metres
• Canoeing at the 1976 Summer Olympics - Men's C-2 1000 metres
• Canoeing at the 1976 Summer Olympics - Men's C-2 500 metres
• Canoeing at the 1976 Summer Olympics - Men's K-1 1000 metres
• Canoeing at the 1976 Summer Olympics - Men's K-1 500 metres
• Canoeing at the 1976 Summer Olympics - Men's K-2 1000 metres
• Canoeing at the 1976 Summer Olympics - Men's K-2 500 metres
• Canoeing at the 1976 Summer Olympics - Men's K-4 1000 metres
• Canoeing at the 1976 Summer Olympics - Women's K-1 500 metres
• Canoeing at the 1976 Summer Olympics - Women's K-2 500 metres
• Canoeing at the 1976 Summer Olympics – Men's C-1 1000 metres
• Canoeing at the 1976 Summer Olympics – Men's C-1 500 metres
• Canoeing at the 1976 Summer Olympics – Men's C-2 1000 metres
• Canoeing at the 1976 Summer Olympics – Men's C-2 500 metres
• Canoeing at the 1976 Summer Olympics – Men's K-1 1000 metres
• Canoeing at the 1976 Summer Olympics – Men's K-1 500 metres
• Canoeing at the 1976 Summer Olympics – Men's K-2 1000 metres
• Canoeing at the 1976 Summer Olympics – Men's K-2 500 metres
• Canoeing at the 1976 Summer Olympics – Men's K-4 1000 metres