British judge Howard Riddle said the extradition request tabled by Swedish lawyers would not breach Assange's human rights, as Assange's defence lawyers had claimed.
The judge also rejected Assange's claim that because of advance publicity surrounding the allegations, including remarks made by the Swedish Prime Minister Fredrik Reinfeldt in which he called Assange "public enemy No. 1," he could not receive a fair trial in Sweden.
"The defence refers to the alleged denigration of the defendant by the Swedish Prime Minister. For this reason ... it is said Mr. Assange will not receive a fair trial. I don't accept this was the purpose of the comment or the effect," Riddle said.
Assange, 39, has been charged with a series of sexual offences against two women during a visit to Sweden in August 2010. Riddle said the allegations of rape and sexual molestation by the women meet the definition of extraditable offenses, and that the Swedish authorities had followed correct procedures in processing their request.
Claes Borgstrom, the lawyer representing the two women, said the judge's ruling was not a surprise.
"It's just too bad that it took so long," Borgstrom said. "[Assange] will probably appeal this decision for some reason that is hard to understand. He claims that he hasn't committed a crime so he should just come here and sort it out. I expect that he will be on Swedish soil before the summer."
Assange denies all charges and says the case is politically motivated due to the controversial work of his Wikileaks organization. He and his lawyers fear extradition to Sweden may result in an eventual extradition to the U.S.
Wikileaks has been releasing a steady flow of official U.S. diplomatic documents -- about 250,000 -- in recent months obtained without official U.S. approval.
In London Thursday, the hearing attracted about a dozen Wikileaks and Assange supporters. They gathered outside the court hours before the hearing with banners and signs reading "Free Julian Assange and Bradley Manning," the U.S. Army private suspected of leaking documents to Wikileaks.
Assange and his high-profile legal team are expected to appeal Thursday's ruling and have seven days in which to do so.
The Associated Press contributed to this report.