Of the total, 4.8GW was installed onshore, with 1.3GW across four countries put in offshore.
WindEurope said onshore installation was concentrated in Germany, with nearly half (2.2GW) the amount installed there. The UK (1.2GW) and France (492MW) also contributed a large chunk to Europe's onshore capacity.
"At least ten EU countries have yet to install a single megawatt this year. On onshore wind, the end of UK renewable obligation scheme will lead to even greater market concentration in Germany and France," said WindEurope chief policy officer, Pierre Tardieu.
Tardieu also warned of a drop-off in offshore installations as investments plummeted from a record €14 billion last year, to €2.9 billion in the first half of 2017.
"The level of finance activity is a concern. Although this won't translate into lower installations for another few years, the industry needs clarity on volumes for the post-2020 period to maintain the current cost reduction trend," Tardieu said.