The unexpected big winner was the anti-Islam Freedom Party, the PVV, which took its number of seats from nine in the last parliament to 24 - its best-ever finish.
The campaign had been dominated by a debate over the economy, which was thought to have eclipsed immigration as an election issue.
But the strong showing for the Freedom Party, led by the controversial Geert Wilders, is a sign that immigration was still a powerful theme, correspondents say.
Mr Wilders has campaigned to stop the "Islamisation of the Netherlands".
He wants the Koran banned, and has suggested a tax on headscarves worn by Muslim women.
I mentioned Geert Wilders briefly in a previous post. It will be interesting to see how this develops.
Islamism presents a real challenge for believers in freedom. On the one hand, it is difficult for us to countenance censorship and restrictions on headwear. On the other, we face an intolerant foreign ideology, which would severely limit individual freedoms if it were to become dominant. Rational debate is the preferred method for combating flawed ideologies, but this route is closed off when 'faith' is involved.