The re-worked version, which includes a rap intro from the 'Nothin' On You' star, appeared on YouTube yesterday ahead of its official release.
BoB's lyrics include: "Had the whole thing mapped out/ You were gonna go to college and pay for bills and I would figure a job out/ Them days are gone."
The remix marks the third time Perry has enlisted a rapper on her single, after Missy Elliot featured on 'Last Friday Night' and Kanye West starred on 'E.T.'
'The One That Got Away' is currently number four on the Billboard Hot 100, giving Perry the most top five songs from one album since George Michael.
If it reaches number one, it will give her a sixth consecutive chart-topper from her Teenage Dream album, beating Michael Jackson's record of five number ones from his Thriller album.
Listen to Katy Perry and BoB's 'The One That Got Away' remix below:
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