The 26-year-old will compete in all six rounds of the Tesco 99 Octane MSA British Rally Championship in one of the team's Group N Lancer Evolution IXs.
Wilks, who previously drove for the works Suzuki team, said: "With Mitsubishi I now have a real chance to challenge for the British Championship.
"I intend to give Mitsubishi 100% to help them to achieve their target of two British titles. I can't wait to get started."
The team has confirmed that both Wilks and team-mate, Gwyndaf Evans, will run on equal status, there being no No 1 and No 2 driver.
Wilks is scheduled to test his car for the first time in April, before the season opener, the Pirelli Rally, on April 20 and 21.
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