Activists from the Extinction Rebellion group have called on the Government to revoke all oil and gas prospecting licences and to urgently enact climate change legislation.
About 20 demonstrators gathered outside the Clayton Hotel Burlington Road in Dublin.
It is the venue for a two-day conference organised by the Irish Shelf Petroleum Study Group.
Protesters poured 15 litres of fake blood outside the main gates of the hotel to represent what they say was the blood on the hands of large oil corporations.
They also set alight a plastic model of the Earth, in a bid to highlight global warming.
The protesters also carried a large fake drilling licence with a bloody handprint, which they say "calls attention to the relationship the Government has with the oil industry".
Demonstrators accuse the oil industry of "derailing regulations" and continuing to drill despite increasing warnings about the consequences of their actions in relation to climate change.
They are also urging the Government to maintain its commitments under the Paris climate change accord.
The protest is the latest in a series of "direct action" demonstrations by the environmental group, which held a week-long campaign of "civil disobedience" earlier this month.