The Australian Hotel's Association has predicted the number of hotel rooms in Canberra would grow by 30 per cent in the next two years, from 6600 to 8800.

That number could yet grow further, with reports this week of Hilton's bid to the ACT government to open its first hotel in the nation's capital.

The association's ACT-branch general manager, Anthony Brierley, welcomed news of Hilton's ambition to open in the ACT, saying it represented recognition of Canberra as a "world-class destination".

Mr Brierley said global operators such as Hilton had huge customer databases, which would allow it to market its Canberra hotel, and the city more broadly, to people across the globe.

He was confident there would be enough demand to meet expected hotel room supply during busy periods, which centred around federal parliamentary sitting weeks and major events, such as Floriade.

But he said occupancy rates dropped off sharply outside those peak periods, with hotel room rates slashed by up to 50 per cent.

He said it was imperative that government and industry act urgently to "stimulate off-peak demand", to ensure Canberra wasn't saddled with hundreds of empty hotel rooms for months at a time.

Attracting more exhibitions and events to Canberra's, such as the Monet:Impression Sunrise exhibition on at the National Gallery of Australia, should be among the key targets for the government, he said.

Latest national figures showed Canberra welcomed a record-high 2.92 million domestic tourists in the 12 months to May 2019, up 170,000 from the 12 months prior.

The visitors injected $1.86 billion into the territory economy, a 21 per cent jump on last year's spending.

Tourism Research Australia data published on Wednesday showed the sector was employing 19,300 people in Canberra at the end of 2017-18, a 9.2 per cent increase on the previous financial year.

That represented the biggest tourism employment growth rate in the nation.

Tourism Minister Andrew Barr said a key function of the government's Major Events Fund was to lure attractions which would drive visitation to Canberra during off-peak periods, traditionally summer and winter. The national gallery's Monet and Cartier exhibitions were both supported by the fund.

The Cartier exhibition drew 89,000 interstate and international visitors during its run last summer, pumping $36 million in the local economy, according figures referenced by Mr Barr.