Sean Miller, 22, went missing from Newtown in the early hours of Saturday February 2, and had not been seen since.
Yesterday Thursday afternoon, Dyfed-Powys Police revealed a body had been found in the search for the 22-year-old.
Formal identification is yet to take place and the coroner has been informed.
A number of people have taken to Mr Miller's Facebook to pay tribute to him.
Shannon Williams posted: "You will be missed will never forget our memories wish I spent more time with you but you will always be in my heart."
Millie Jones said: "R.I.P Sean S Miller can’t believe your gone you will be missed and never forgotten like shannon said always remember our memories and wished we had more fly high."
Jon Wilkins added: "Rest in peace buddy, you'll be missed!"
And Holly Jo Clay posted: "Your one in a million, your a very kind, honest, happy, lovin person to be around!"
A search had taken place for six weeks, after Mr Miller was last seen on a night out with friends on February 2.
Since he was last seen neither his bank accounts or Facebook page had been used, and a large search had taken place involving Dyfed-Powys Police, Mid and West Wales Fire and Rescue Service and the National Police Air Service.
On February 25, a hooded jumper and a trainer belonging to Mr Miller was found near the river.
Earlier this week his brother Justin and sister Natasha, issued fresh calls for information in a bid to discover what had happen to him.
On Thursday afternoon, a spokeswoman for Dyfed-Powys Police confirmed: "It is with sadness that Dyfed-Powys Police can confirm a body has been found during the search for missing Sean Miller, from Newtown.
"Our thoughts are with his family, who have been informed of the development. They are being supported by specially trained officers at this time.”