John Carl Warnecke (born 1919) is an architect based in San Francisco, California who designed numerous monuments and structures in the international style, among others. He was an early proponent of contextual architecture.
Warnecke is known for the design of the 33 Thomas Street (AT&T Long Lines Building) in Manhattan, New York, United States, and for the design of the John F. Kennedy memorial at Arlington National Cemetery. He also designed the North Academic Center at CCNY.
Warnecke's firm, John Carl Warnecke & Associates, designed the Hart Senate Office Building, the New Executive Office Building, the Howard T. Markey National Courts Building in Washington, DC, and 650 Fifth Avenue in New York City. He also known for helping John F. Kennedy's administration to help save the historic buildings of Lafayette Square.
The firm also designed numerous buildings at the University of California, Berkeley.  Other important commissions include the Hawaii State Capitol and the First Alabama Bank Building in Birmingham, Alabama.