Festival dijadwalkan dari 24 Jun hingga 04 Jul 2004 (10 hari).
Summerfest berlangsung di Milwaukee, United States. Berikut adalah alamat lengkap festival: Henry Maier Festival Park; Milwaukee, Wisconsin, United States
Maroon 5, Kenny Chesney, Skillet, Nickelback, Shinedown, Three Days Grace, Styx, John Mayer, Tim McGraw, Indigo Girls, Jason Mraz, 3 Doors Down, 311, Kid Rock, Kenny Wayne Shepherd.
Genre dan sub-genre yang paling populer dari edisi sebelumnya adalah:
rock
pop
punk
alternative
alternative rock
hard rock
indie
classic rock
metal
pop rock
post-grunge
indie rock
acoustic
alternative metal
grunge
emo
punk rock
nu metal
rnb