MK5 may refer to:

• Deadly Alliance, the fifth game in the Mortal Kombat series
• Mario Kart DS, the fifth game in the Mario Kart series
• MK5, an English postcode district

• California State Route 3 (1934)
• California State Route 3 (1964)
• California State Route 32
• California State Route 32 (1964)
• California state route 33
• California State Route 33 (1964)
• California State Route 34 (1964)
• California State Route 35 (1934-1964)
• California State Route 35 (1934–1964)
• California State Route 35 (1964)
• California State Route 36
• California State Route 36 (1964)
• California State Route 371
• California State Route 37 (1964)
• California State Route 38 (1964)
• California State Route 39 (1964)
• California State Route 395 (1964)
• California State Route 399
• California State Route 39 (pre-1964)
• California State Route 3 (pre-1964)
• California State Route 40 (1964)
• California State Route 405 (1964)
• California State Route 41 (1964)
• California State Route 4 (1964)
• California State Route 42