Since the debut of Jeopardy! in 1964, several different songs and arrangements have served as the theme music for the show, most of which were composed by Merv Griffin. The main theme for the original Jeopardy! series was "Take Ten", composed by Griffin's wife Julann. The All-New Jeopardy! opened with "January, February, March" and closed with "Frisco Disco", both of which were composed by Griffin himself.

The best-known theme song on Jeopardy! is "Think!", originally composed by Griffin under the title "A Time for Tony", as a lullaby for his son. "Think!" has always been used for the 30-second period in Final Jeopardy! when the contestants write down their responses, and since the syndicated version debuted in 1984, a rendition of that tune has been used as the main theme song. "Think!" has become so popular that it has been used in many different contexts, from sporting events to weddings.

Griffin estimated that the use of "Think!" had earned him royalties of over $70 million throughout his lifetime. "Think!" led Griffin to win the Broadcast Music, Inc. (BMI) President's Award in 2003, and during GSN's 2009 Game Show Awards special, it was named "Best Game Show Theme Song". In 1997, the main theme and Final Jeopardy! recordings of "Think!" were rearranged by Steve Kaplan, who served as the show's music director until his December 2003 death. In 2008, Chris Bell Music and Sound Design overhauled the Jeopardy! music package for the show's 25th anniversary.

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