New Japan started the IWGP plan in 1981. After the last title defense against Stan Hansen, Inoki abandoned the NWF Heavyweight Title. All other titles in New Japan were also abandoned : WWF North American Heavyweight (held by Seiji Sakaguchi), NWA North American Tag (Choshu & Choshu), NWF North American Heavyweight, Asian Heavyweight (both by Singh), and Asian Tag (Singh & Umanosuke Ueda). Also, Abdullah the Butcher, who was the top foreign star of All Japan, jumped to New Japan, announcing his participation to the IWGP.

In 1983, the first IWGP final championship was finally held. Participants included Inoki, Killer Khan, Rusher Kimura (Asian representatives), Andre the Giant (Canada), Big John Studd, Hulk Hogan (U.S.), Canek, Enrique Vera (Mexico), Otto Wanz, and Akira Maeda (Europe). In final, Inoki was knocked out by Hulk Hogan and carried to hospital.

After defeating Hogan by count out of the ring in 1984 and 1985, Inoki kept winning the tournament until 1987. See the detailed history of the first IWGP, courtesy of The Great Hisa's Puroresu Dojo.

In 1987, the championship became a regular title after Inoki defeated Masa Saito in the tounrnament final. Inoki defended the IWGP Heavyweight Title for four times against Bam Bam Bigelow, Dick Murdoch, Steve Williams, and Riki Choshu. However, he vacated the title after breaking his left leg.

Inoki challenged the second champion Fujinami and wrestled 60 minutes to a draw. As the title went away from Inoki, Inoki also started going away from the main events.

The IWGP title was later held by Choshu, Great Muta, Shin'ya Hashimoto, and Keiji Mutoh, and became the symbol of New Japan's top star.

See the detailed history of the title, courtesy of The Great Hisa's Puroresu Dojo.