US District Judge Brett Ludwig dismissed Trump’s federal lawsuit, which had asked the court to order the state’s Republican-controlled legislature to name him the winner over Joe Biden.
A recount in the state confirmed last month that Mr Biden had beaten Mr Trump by more than 20,000 votes.
Dismissing the case Judge Ludwig said that Mr Trump’s legal arguments “fail as a matter of law and fact”, reported the Associated Press.
In the Wisconsin Supreme Court case, which are rarely held on weekends, Mr Trump has asked justices to disqualify more than 221,000 votes in the state’s two most heavily Democratic counties.
But he has not challenged any votes in counties that he won himself.
“This lawsuit, Mr Troupis, smacks of racism,” Justice Jill Karofsky told Mr Trump’s lawyer, Jim Troupis.
“I do not know how you can come before this court and possibly ask for a remedy that is unheard of in US history.”
The judge then branded the request as “not normal.”
The Wisconsin Supreme Court, which had previously refused to hear the case before it went through lower courts, agreed to hear the case on Friday with the electoral college vote due on Monday.
Mr Trump’s lawyers have suffered a string of legal defeats in courtrooms across the country as they try and help the president hold onto power.
His hopes were dealt a crushing blow on Friday night when the US Supreme Court refused to hear a case brought by the Texas attorney general that wanted justices to overturn results in four battleground states.