Rock Band 2 is the sequel to the 2007 musical simulation game Rock Band and offers similar gameplay. Directly competing with Guitar Hero: World Tour, the game allows different people to play together as in a band, with the same peripherals as the first game: lead guitar, bass guitar, microphone and a drum set.

The new drum and guitar controllers for this version, bundled or sold separately, have been revised and older controllers are also supported. The guitar controller, modelled after the Fender Stratocaster, has five additional fret buttons near the neck, for fast fingertapping sessions. There is also an effect switch to toggle between five different effects. Players use the instruments to match notes on the screen, divided in different portions for different instruments, along with the lyrics for the singer who need to match the pitch.

The original game's Solo Tour mode and the multiplayer Band World Tour mode have been merged into a single Tour mode where up to four players can cooperate, both local and online (PS3/Xbox 360). Band leaders are no longer necessary and instruments can be swapped at will. From this mode, three options are available: Start Tour (regular tour mode), Tour Challenge (different challenges), and Battle of the Bands (compete against other bands online through score tracking - not on the PS2). The game includes a training mode for the different instruments, as well as a freestyle mode for drummers where they can drum along with custom mp3 files (Xbox 360/PS3). Other modes and modifiers for the regular game modes can be selected from an Extras menu.

The in-game characters can also be customized and 84 tracks are included on the disc, with many more as downloadable content (not on the PS2). It is also possible to transfer the songs of the first Rock Band (for a price), and downloadable content as well as the two track packs.