IWGPヘビー級王座
Wrestle Kingdom IV was main evented by Shinsuke Nakamura defending the IWGP Heavyweight Championship against Yoshihiro Takayama. This was the first match between the two in six years and was billed as a rematch from the 2004 January 4 Tokyo Dome show. That match saw Nakamura defeat Takayama for the NWF World Heavyweight Championship, which was afterwards retired, leading to Takayama announcing that if he were to win the IWGP Heavyweight Championship at Wrestle Kingdom IV, he would immediately retire the title.