Terrorism, power prices, water and economic growth will be topics for discussion when the prime minister dines with premiers and chief ministers in Hobart on Thursday night.
Malcolm Turnbull and state and territory leaders will meet for the Council of Australian Governments in the Tasmanian capital on Friday.
But the evening before the main meeting will be informal talks between the leaders, as well as a special meeting between Mr Turnbull and Murray-Darling Basin premiers.
The last COAG in December decided to hold a regular side meeting of basin-state leaders which would discuss a "credible and balanced pathway" to implementing the basin plan package agreed in 2012.
News that makes sense
Your trusted source for staying up-to-date with the world around you. Get free daily news updates and analysis, straight to your inbox.
Federal Water Minister Barnaby Joyce has initiated a review to examine how an extra 450 gigalitres of water - on top of the 2750Gl target - for the environment can be recovered, without negatively affecting basin communities.
The review will report in December.
Environmental, indigenous and community groups have called for the Murray-Darling Basin Plan to be delivered on time and in full.
The full COAG meeting on Friday will discuss an overhaul of the parole system following the Melbourne terrorism incident, as well as bolstering co-operation on cyber security and infrastructure protection.
A key topic for discussion will be the final report of a review of the national electricity market by chief scientist Dr Alan Finkel.
Dr Finkel will present a range of options to deliver better reliability of energy, keep downward pressure on power bills and cut carbon emissions.
The federal government is widely expected to back a "low emissions target", mandating a percentage of power each year be generated from sources below a certain emissions level.
