Renaud-Roy, from St-Roch-des-Aulnaies, Que., finished off her perfect run with a win in the gold-medal match over Russia's Valeri Shishmareva.
"Everything went really well today," Renaud-Roy said. "I won all four of my bouts very quickly, all on the ground.
"I admit that the category I was in wasn't very tough today; there definitely weren't any really excellent judokas present. It's a European Cup, so there will always be less talent than at a World Cup event."
On the men's side, Zachary Burt of Whitby, Ont., came away with a bronze medal in the under-81-kilogram event after winning three of his four matches. After losing his third bout to France's Antoine Jeannin, he won his bronze-medal match against Russia's Ivan Pakhomov.
"I had hoped to make the finale, but I just wasn't at my best today," Burt said. "In the end I was happy to come back and win the bronze medal."
Elsewhere, Martin Rygielski of Waterloo, Ont., (over-100 kg), lost all four of his bouts.