Campbell was part of the Hull's promotion-winning squad in 2007/08 and is hopeful his new team can repeat the feat next season.
The 29-year-old striker told Hull's official website: "I'm delighted to be a Tiger again and hopefully it can go the same way as it did last time with us winning promotion to the Premier League."
"I'm looking forward to playing at the KCOM Stadium again and I can't wait to get started."
| @FraizerCampbell speaks to #TigersTV for the first time following his return to the Club https://t.co/3GMtsKK9hl #WelcomeBackFraizer
— Hull City (@HullCity) 19 de julho de 2017