Route 338, or Highway 338, may refer to:

• Manitoba Provincial Road 338
• Prince Edward Island Route 338
• Quebec Route 338

• Main road 338 (Hungary)

• Japan National Route 338

• Highway 338 (Thailand)

• Georgia State Route 338
• Kentucky Route 338
• Maryland Route 338 (former)
• Nevada State Route 338
• New Mexico State Road 338
• New York:
  • New York State Route 338 (disambiguation)
  • County Route 338 (Erie County, New York)
  • County Route 338 (Saratoga County, New York)
  • County Route 338 (Wayne County, New York)
• Ohio State Route 338 (former)
  • Ohio State Route 338J (former)
• Pennsylvania Route 338
• Puerto Rico Highway 338
• Tennessee State Route 338
• Texas:
  • Texas State Highway 338
  • Texas State Highway Loop 338
• Virginia State Route 338
• Wyoming Highway 338