List of highways numbered 78
The following highways are numbered 78:
International
- Asian Highway 78
- European route E78
Australia
- Waterfall Way – New South Wales State Route B78
China
- G78 Expressway
Greece
- EO78 road
Iran
- Road 78
Korea, South
- Gukjido 78
New Zealand
- New Zealand State Highway 78 – New Zealand's shortest State Highway
Philippines
- N78 highway
United States
- Interstate 78
- U.S. Route 78
- Alabama State Route 78
- * County Route 78
- Arizona State Route 78
- Arkansas Highway 78
- California State Route 78
- Colorado State Highway 78
- Connecticut Route 78
- Florida State Road 78
- * County Road 78
- ** County Road 78A
- ** County Road 78B
- * County Road 78
- ** County Road 78A
- * County Road 78
- ** County Road 78A
- Georgia State Route 78
- Hawaii Route 78
- Idaho State Highway 78
- Illinois Route 78
- Iowa Highway 78
- K-78
- Kentucky Route 78
- Louisiana Highway 78
- Maryland Route 78
- Massachusetts Route 78
- M-78
- Minnesota State Highway 78
- * County Road 78
- * County Road 78
- Missouri Route 78
- *Missouri Route 78
- Montana Highway 78
- Nebraska Highway 78
- * Nebraska Spur 78B
- * Nebraska Spur 78C
- * Nebraska Spur 78D
- * Nebraska Spur 78E
- * Nebraska Spur 78F
- * Nebraska Spur 78H
- * Nebraska Spur 78J
- * Nebraska Recreation Road 78K
- Nevada State Route 78
- New Hampshire Route 78
- County Route 78
- New Mexico State Road 78
- New York State Route 78
- * County Route 78
- * County Route 78
- * County Route 78
- * County Route 78
- * County Route 78
- * County Route 78
- * County Route 78
- * County Route 78
- * County Route 78
- * County Route 78
- * County Route 78
- * County Route 78
- * County Route 78
- North Carolina Highway 78
- Ohio State Route 78
- Oklahoma State Highway 78
- Oregon Route 78
- Pennsylvania Route 78
- Rhode Island Route 78
- Tennessee State Route 78
- Texas State Highway 78
- * Texas State Highway Spur 78
- * Farm to Market Road 78
- * Urban Road 78
- Utah State Route 78
- Vermont Route 78
- Virginia State Route 78
- Wisconsin Highway 78
- Wyoming Highway 78
- U.S. Virgin Islands Highway 78