The 1948 Republican National Convention was held at the Municipal Auditorium, in Philadelphia, Pennsylvania, from June 21 to 25, 1948.

New York Governor Thomas E. Dewey had paved the way to win the Republican presidential nomination in the primary elections, where he had beaten former Minnesota Governor Harold E. Stassen and World War II General Douglas MacArthur.

In Philadelphia he was nominated on the third ballot over opposition from die-hard conservative Ohio Senator Robert A. Taft, the future "minister of peace" Stassen, Michigan Senator Arthur Vandenberg, and California Governor Earl Warren.

One of the decisive factors in convening both major party conventions in Philadelphia that year was that Philadelphia was hooked up to the coaxial cable, giving the ability for two of the three then-young television networks, NBC and CBS, to telecast for the first time live gavel-to-gavel coverage along the East Coast.

Dewey had a long list of potential running mates, including his 1944 running mate, Senator John Bricker of Ohio, Representative Charles Halleck of Indiana, former Governor Harold Stassen of Minnesota, and California Governor Earl Warren.