Two Greens MPs have been arrested in central Queensland and charged with trespass, following a protest against the Adani mine.

NSW state MPs Jeremy Buckingham and Dawn Walker were taking part in a blockade of the Carmichael coal mine rail construction site at Belyando when they were arrested on Wednesday morning.

Protesters chanted "Stop Adani" while police asked them all for identification.

The protest started about 4.30am Queensland time, and the upper house MPs were arrested two hours later.