Through social media, the 46-year-old Puerto Rican artist, whose real name is William Omar Landrón Rivera, posted a photo of his hand with a wristband from Orlando Health hospital.
"Today I do, but tomorrow I won't have cancer. Good wishes are well received," Don Omar stated in his publication. "See you soon."
He did not disclose further details about his diagnosis or the type of cancer he has.
Don Omar immediately received messages of support on his post.
"God bless you brother. You'll be fine. We're here for whatever!" commented fellow reggaeton artist Zion.
Olga Tañon also commented, "My beautiful boy, you are a warrior of a thousand battles and you will win this one too of course!"
He is set to perform in Los Angeles during his "Back to Reggaeton" tour on August 20. As of now, the tour has not been canceled.
Known as the "King of Reggaeton," Don Omar has received 2 Latin Grammys and 13 nominations, making him one of the most influential urban music artists.
He has also appeared in the "Fast & Furious" franchise playing the role of Rico Santos. Some of his songs were also featured in the movies.