A lacklustre campaign has produced a fragmented parliament, with more than its share of political unknowns and re-treads from national politics.
By William Horsley
BBC European affairs correspondent
The new European parliament is an unpredictable mixture of believers in a united Europe and Eurosceptics.
As before, there is a working majority of conservative, and liberal or other pro-business members.
The EU has a tough time connecting to many Europeans
Europe's Social Democrats remain the next largest grouping.
The main influence of the new member-states in the east has been to strengthen the centre-right, as well as the Eurosceptics who seek to stop the march towards a "political union".
The parliament still lacks well-known political figures to grab the attention of the media and people of Europe.
The parliament's work will go on without any major change of direction.
It will frame new laws on industrial chemicals and food labelling, and enforce health and safety standards and the EU's "single market" rules.
The voters have exercised their right to rebuke their national governments, inflicting defeats on them from Berlin to Paris and from Warsaw to London.
But the election was not really fought on European issues.
The real loser from the record low turnout of 45% is the image of the parliament itself.
It shows that voters still lack respect for the parliament which makes laws for the whole EU and claims to represent the people's voice.
With more than half a million voters on average for each seat, it has been hard for Members of the European Parliament to get themselves widely known.
The obligation on members to commute often between different parliament buildings in Brussels and Strasbourg, as well as petty scandals about members' abuse of their lavish expense accounts, have harmed their public image.
And those things drove many formerly active MEPs to quit, and not seek re-election.
Tough battles ahead
More trouble probably lies ahead. EU government leaders aim to finalise a European Union constitution at a summit meeting later this week.
It proposes to give the parliament a bigger role than ever, as part of what is intended to be a functioning pan-European democracy.
The parliament would win new powers to make EU regulations, decide the EU budget and take on more of the functions carried out by national parliaments.
But this election result has again thrown doubt on the prospects for creating such an international democracy on a continent with many different languages.
There was almost no cross-border campaigning for the elections.
Voters have again shown that they see the EU as remote.
The result is a patchwork of party groups, chosen by less than half the EU's voters.
It looks largely like a protest vote by citizens annoyed by the record of their governments over the Iraq war, or on other issues unconnected to the work of the European parliament.
And it will take months for the 732 newly-elected members from 25 states even to get to know each other.