The lower court in Moscow ordered the website to take down information about the war in Ukranian.
The Wikimedia Foundation said in a statement that removing the information would violate people's rights to free expression. The appeal was filed on June 6.
The country has no jurisdiction over the online encyclopedia, which is available in 300 languages. It hasn't complied with any of Russia's demands so far.
Wikimedia was fined by the Russian court for refusing to remove "untrue socially important information" from their pages.
Russian prosecutors said that the website was a tool for unfair anti-Russian sentiment.
Wikimedia said that some of the articles the court took issue with were "fact-based knowledge."
More than 140 million people would be denied access to the encyclopedia if it were blocked in Russia.
The new "disinformation" laws signed by President Putin in March allow authorities to punish anyone who gives false information about the war with up to 15 years in prison or fines of up to 5 million rubles.
Stephen LaPorte, Associate General Counsel at the Wikimedia Foundation, said in the organization's statement that the court's decision shows a disparity between the well-sourced, verified knowledge of Wikipedia and the Russian government's definition of disinformation.
In a time of crisis, the government is targeting important information. Everyone has the right to knowledge access and free expression.
The articles are edited and checked by hundreds of thousands of people.
Insider requested a comment from the Wikimedia Foundation.
Russian access to most social media platforms and news outlets has been cut off since Russia invaded Ukraine.
The invasion is said to be a special military operation to liberate the people of the Donbas region. Putin said in his Victory Day speech that the war is part of a larger effort by Russia to defy the US.