The 19-year-old, who recently signed a new contract with the Whites, links up with the Blades until the end of the season in an attempt to gain more first-team experience.
Poleon, the leading scorer in the Leeds Under-21 side with six goals, has made seven senior appearances for the Elland Road club this term, while also enjoying a successful loan spell at Bury.
He told Leeds' official website: "It's another chance to get some more experience and play first-team football.
"Sheffield United are near the top and I want to help them kick on and push for promotion."
- Sports & Recreation