Ennis McBride, 53, was convicted of intimidating behaviour towards the former X Factor winner at South Tyneside Magistrates' Court today (September 11).
The Stockport resident had been accused of appearing at the singer's home in South Shields last year, and posting several derogatory statements about him on Twitter.
He was fined £1,000, along with paying a further £915 in costs, reports The Journal.
McElderry appeared in court to give evidence in the case, and stated that he had been left scared and intimidated by the ordeal.
McBride was given a five-year restraining order, which prevents him making any contact with McElderry or his mother.
District Judge Roger Elsey said of McBride: "He has given evidence but has not been a compelling witness and lacked credibility.
"He totally lacked insight into the impact of his actions on the complainants."
Joe McElderry released his fourth studio album Here's What I Believe on Monday.
Watch the singer talk to Digital Spy about The X Factor below: