The International Wrestling Grand Prix (IWGP) Heavyweight Championship is the top title in Japanese promotion New Japan Pro Wrestling. It was created in 1987 with NJPW founder Antonio Inoki defeating Masa Saito in the finals of the annual IWGP Tournament. There have been a total of 23 recognized champions, who have had a combined 53 official reigns.
- New Japan Pro Wrestling
- Champion history - History of the wrestlers who have held the belt.
- Title matches - Matches in which the title was defended.
- Champion gallery - A gallery of all champions.