Amphenol Corporation is a major producer of electronic and fiber optic connectors, cable and interconnect systems such as coaxial cables. Amphenol is a portmanteau from the corporation's original name, American Phenolic Corp.

Amphenol was founded in Chicago in 1932 by entrepreneur Arthur Schmitt, whose first product was a tube socket for radio tubes (valveholder bases). Amphenol expanded significantly during World War II, when the company became the primary manufacturer of connectors used in military hardware, including airplanes and radios. From 1967 to 1982 it was part of Bunker Ramo Corporation.

Amphenol's revenues in 2010 were $3.55 billion. The company sells its products into diverse electronics markets, including military-aerospace, industrial, automotive, information technology, mobile phones, wireless infrastructure, broadband, medical, and pro audio. Operations are located in more than 60 locations around the world. The company is included in the S&P Midcap 400 index. Amphenol's Chairman is Dr. Martin H. Loeffler. Chief Executive Officer is R. Adam Norwitt.

Amphenol's world headquarters is located in Wallingford, Connecticut. The largest division of Amphenol is Amphenol Aerospace (formerly Bendix Corporation) in Sidney, New York. This is the birthplace of the MIL-DTL-38999 cylindrical connector. Amphenol engineers also invented the commonly used BNC connector ("Bayonet Neill-Concelman").

Amphenol Cables on Demand, another division of Amphenol launched in December 2006, specializes in distributing standard cable assemblies via their e-commerce storefront. They sell more than 2500 audio, video, computer, and networking cables. Offices are located in New York, California, Florida, and China.