38 may refer to:

• 38 (number)
• 38 BC
• AD 38
• 1938
• 2038

• Strontium, an alkaline earth metal in the periodic table
• 38 Leda, an asteroid in the asteroid belt

• .38, a caliber of firearms and cartridges
  • .38 Special, a revolver cartridge
• Thirty-Eight: The Hurricane That Transformed New England, a 2016 book by Stephen Long
• "Thirty Eight", a song by Karma to Burn from the album Almost Heathen, 2001