List of highways numbered 320

Canada

• Newfoundland and Labrador Route 320
• Nova Scotia Route 320
• Saskatchewan Highway 320

  China

• China National Highway 320

  Costa Rica

• National Route 320

  India

• National Highway 320

  Japan

• Japan National Route 320

  United States

• U.S. Route 320
• Arkansas Highway 320
• Connecticut Route 320
• Florida State Road 320
• * County Road 320
• Georgia State Route 320
• Hawaii Route 320
• Kentucky Route 320
• Louisiana Highway 320
• Maryland Route 320
• Montana Secondary Highway 320
• Nevada State Route 320
• New Mexico State Road 320
• New York State Route 320
• Ohio State Route 320
• Pennsylvania Route 320
• Puerto Rico Highway 320
• Tennessee State Route 320
• Texas:
• * Texas State Highway 320
• * Texas State Highway Loop 320
• * Farm to Market Road 320
• Utah State Route 320
• Virginia State Route 320
• Wyoming Highway 320