Pfeiffer may refer to:

• Pfeiffer syndrome, a rare genetic disorder characterized by the premature fusion of certain bones of the skull
• Infectious mononucleosis, also known as the kissing disease, or Pfeiffer's disease

• Pfeiffer University, Misenheimer, North Carolina, U.S.
• Carl A. Pfeiffer, a German piano manufacturer
• Pfeiffer Vacuum, a German manufacturer of vacuum pumps

• Pfeiffer, Arkansas, U.S.
• Pfeiffer, Ohio, U.S.
• Pfeiffer Lake, Minnesota, U.S.
• Pfeiffer Big Sur State Park
• Julia Pfeiffer Burns State Park

• Pfeiffer (surname)
• Pfeiffer effect, an optical phenomenon

• Pfeiffer House (disambiguation)
• Pfeifer, a surname
• Pfeffer, a surname