Disclose based its report on a classified note from France's military intelligence service saying that French-made weapons, including artillery, tanks, ships and fighter-bomber jets, "may have been used to commit war crimes."
The French media nonprofit said the report was given to President Emmanuel Macron during a meeting of a restricted defense committee held at the presidential office in October.
Entitled "Yemen: security situation," it details the positioning of French-made weapons in the conflict. "It demonstrates that hundreds of thousands of civilians live under the threat of these arms, and provides information that allows us to demonstrate that some of these weapons may have been used to commit war crimes," Disclose said. "The French government is today aware of the risk of this," it added.
The Saudi-led coalition has fought Yemen's Houthi rebels since 2015 in a conflict that has killed tens of thousands of people.
The French government did not immediately respond to an email seeking comment. France previously said its weapons were only used defensively.
Reacting to the report, Amnesty International urged France "to immediately suspend all arms transfers that could be used by any of the warring parties in Yemen - once and for all."