K. Hariharan may refer to:

• K. Hariharan (director), Indian film director
• Krishna Hariharan (born 1955), Indian Test cricket umpire

• Complex Regional Pain Syndrome
• Complex representation
• Complex sales
• Complex script
• Complex sentence
• Complex societies
• Complex society
• Complex specified information
• Complex structure
• Complex structure deformation
• Complex structure on a real vector space
• Complex system
• Complex systems
• Complex text layout
• Complex trigonometric polynomial
• Complex variable
• Complex vector bundle
• Complex vector space
• Complex wavelet transform
• Compliance
• Compliance costs
• Compliance (physiology)
• Compliance testing
• Compliance Week
• Complicated (Avril Lavigne song)