Sihanouk Boulevard (Khmer: មហាវិថីព្រះសីហនុ) is a central boulevard of Phnom Penh which is the capital of Cambodia. The boulevard crosses the city in an east–west direction. It is named in honour of the late King Norodom Sihanouk, one of the country's greatest kings.

It crosses with the east–west Norodom Boulevard at Independence Monument and near Wat Lanka. It crosses Samdech Hun Sen Boulevard.