Gareth Bale netted his third goal of the tournament in the second half to put the icing on the cake for Wales, who topped their pool after England drew 0-0 with Slovakia in Saint-Etienne.
Bale became the first player since Milan Baros and Ruud van Nistelrooy in 2004 to score in the opening three matches of a European Championship and will have no intention of slowing down as Wales embark on their knockout campaign.
The Dragons soared into a two-goal lead inside 20 minutes as Aaron Ramsey dinked the ball over Igor Akinfeev, before Neil Taylor scored his first goal for his country. And Bale gave the scoreline a deserved convincing gloss when he prodded the ball beyond Akinfeev with the outside of his left boot after getting on the end of a Ramsey ball into the box.
Wales will now face the third-placed side from either Group A, C or D in the last 16 in Paris on Saturday after pipping England to top spot.