Victorian Liberal candidate Aaron Lane has been forced to resign over a series of crude comments he made on social media.

Aaron Lane was a former Young Liberals president and research fellow at the Institute of Public Affairs (IPA).

He was preselected in May to contest the Western Victoria region in the Upper House.

It has since emerged that he had sent a string of homophobic and sexist tweets since 2012.

Dr Napthine said the comments were completely inappropriate.

"There's no place in my team for homophobic comments, there's no place in my team for totally inappropriate comments," he said.

"I believe that it's time for Mr Lane to step down."

The Liberal Party released a statement saying that although Mr Lane apologised unreservedly for his comments, the behaviour in question would not be tolerated.

Mr Lane apologised on 774 ABC Melbourne saying his tweets had been taken out of context.

"This afternoon I made the the decision to resign as a Liberal candidate," he said.

"It was an extremely difficult decision but I think it was the right thing to do in the circumstances.

"I really regret the fact that these tweets were there, I regret the offence, I'm deeply embarrassed by it and I'm ashamed of it.

"We've all said things that we wish we hadn't and that's the underlying thing here."

The executive director of the IPA, John Roskam, said Mr Lane should not have written the tweets.

"What he did is entirely inappropriate. It's wrong. He's regretful," he said.