Labor leader Mark McGowan has conceded defeat in the West Australian elections.

Mr McGowan says he rang the Premier Colin Barnett and congratulated him on the win.

"It's been a hard fought campaign," he said.

"The truth of the matter is, it was hard to win. We did our best in the circumstances that were presented to us, and I think we did a good job."

On current counting, Labor has won only 18 seats and may pick up one more, down from the 26 they held.

It is a landslide victory for the Liberals who have won 31 seats and are predicted to gain two more while the Nationals have won six seats and could pick up one more.

The Liberal Party's Elani Evangel looks to have taken Perth and Nathan Morton has won Joondalup.

The Liberals have also picked up Balcatta and Churchlands and retained Morley.

Senior Labor MP Michelle Roberts' formerly safe Labor seat of Midland is under threat, along with the retiring former Opposition Leader, Eric Ripper's seat of Belmont.

Mr Ripper says while Mr McGowan has run an excellent campaign, it was always going to be tough to win.

"It's just a very tough ask to defeat a government seeking a second term when the economy is strong and of course when there are other factors outside state politics that will play their part," he said.

The deputy federal Opposition Leader Julie Bishop says the Prime Minister Julia Gillard had a negative effect on Mr McGowan's campaign, despite his efforts to distance himself from his federal counterpart.

"Everybody says Mark McGowan ran a good campaign but Labor's brand in this state is toxic and there is a Gillard factor," she said.

"Imagine what'd happen if Julia Gillard had campaigned here, it'd be a 15 % swing against Labor so we have to look at the Gillard factor.

"West Australians felt that she'd declared war on this state with the mining tax, the carbon tax."

Former Labor Minister Alannah MacTiernan says she thinks Julia Gillard should go.

"At a personal level, I think Julia Gillard is a very decent person but you can't be a leader if people don't want you as a leader, and that unfortunately has to be a reality that our Prime Minister needs to take on board," she said.

"I know it may be very unfair and very horrible but that is the reality out there; people do not buy Julia Gillard as a leader."

Ms MacTiernan says Labor should change its leadership before the federal election.

"You cannot go out doorknocking in Armadale and go out to the shopping centres in Forrestfield and Perth and get Labor people telling you that they'll vote for Labor this time at the state election but there's no way they'll vote for Labor federally," she said.

"I mean you can't ignore that."

Federal Labor MP Gary Gray has rejected Ms MacTiernan's call for Julia Gillard to go.

"What we hear from Alannah is the kind of emotion that characterises a very bad result," he said.

"It doesn't characterise deep and thoughtful analysis."

Nationals

Nationals leader Brendon Grylls risky move to shift to the Labor-held seat of Pilbara has paid off with a 15 per cent swing.

The Nationals Wendy Duncan has picked up Kalgoorlie.

The Premier Colin Barnett has maintained the Liberals will still govern in an alliance with the Nationals.

The Treasurer Troy Buswell is backing this up.

"Even if we were statistically able to, the Premier's given several very clear indications that he wants to retain the partnership that we've enjoyed with the National Party over the last couple of years," he said.

"I think it's been a good partnership and I think it's led to good government for the state."

"I think they're (the Nationals) are an important part of the government so I don't see that that would change.

"They have a number of senior Cabinet ministers, they are very active participants in the process of government and I don't think that will change based on the outcome of the election tonight."