The following highways are numbered 170:

Canada

• New Brunswick Route 170
• Prince Edward Island Route 170
• Quebec Route 170

Costa Rica

• National Route 170

Japan

• Japan National Route 170

United States

• Interstate 170 (Missouri)
• Interstate 170 (Maryland) (former)
• U.S. Route 170 (former)
• Alabama State Route 170
• Arizona State Route 170 (former)
• Arkansas Highway 170
• California State Route 170
• Colorado State Highway 170
• Georgia State Route 170 (former)
• Illinois Route 170
• K-170 (Kansas highway)
• Kentucky Route 170
• Louisiana Highway 170
• Maine State Route 170
• Maryland Route 170
• M-170 (Michigan highway) (former)
• Nevada State Route 170
• New Jersey Route 170 (former)
• New Mexico State Road 170
• New York State Route 170
  • New York State Route 170A
• Ohio State Route 170
• Pennsylvania Route 170
• South Carolina Highway 170
• Tennessee State Route 170
• Texas State Highway 170
  • Texas State Highway Loop 170
  • Farm to Market Road 170
• Utah State Route 170 (former)
• Virginia State Route 170
• Washington State Route 170
• Wisconsin Highway 170
• Wyoming Highway 170

Territories

• Puerto Rico Highway 170