The arrests came after a series of raids across the city earlier today and yesterday.
A garda spokesman said the “intelligence led” operations were targeting drug trafficking networks which are operating at an international level.
During one of the raids in Beaumount, North Dublin yesterday, a number of bottles of wine and champagne were located and seized by officers.
Following technical examination it is suspected the seized bottles contain cocaine in liquid form.
The cocaine seized is estimated to have a street value in excess of €150,000.
One man (20s) was arrested at the scene on suspicion of drug trafficking and is currently being detained at Ballymun Garda station.
In another operation yesterday, officers attached to the Garda National Drugs and Organised Crime Bureau, supported by a Special Crime Task Force, intercepted a vehicle travelling on the M50 motorway.
The investigation team also searched premises located in Palmerstown, Dublin and the Dublin 2 area.
A garda spokesman said: "In the course of these searches, the investigation team located and seized substances believed to include cannabis, cocaine and heroin, which are now subject of forensic examination.
“At this time, it is the estimated street sale value of the drugs seized, is in excess of €2 million.
"A substantial quantity of cash, the extent of which is to be established, believed to be the proceeds of drug trafficking, was also located and seized.
“Other items, including equipment used for the purpose of money counting and vacuum packing money and drugs along with communications devices and a substantial quantity of relevant documentation, were also located and seized.”
Five men – aged between 20s and 40s - were arrested on suspicion of involvement in drug trafficking and are currently detained at various garda station located in Dublin.
A sixth male suspect (30s) was arrested, today, in a follow up operation in the Dublin 2 area.
This suspect was also arrested on suspicion of drug trafficking and is currently detained at Donnybrook Garda station.
Assistant Commissioner John O’Driscoll, who is assigned responsibility for heading Garda Síochána initiatives designed to tackle organised and serious crime today said:
"The outcome of operational activity undertaken by the Garda National Drugs and Organised Crime Bureau, supported by a number of other specialised units within the Garda Síochána, over the past twenty-four hours, is very significant and reflects exceptional policing skills along with dedication and bravery on the part of the personnel involved.
“Arising from the global aspect of the drug supply networks that deliver drugs to cities and towns in Ireland, Northern Ireland, the UK and elsewhere in Europe, the Garda Síochána has forged particularly strong and productive relationships with law enforcement entities in many countries across a number of continents.
“Again today the Garda Síochána and the people of Ireland reap the benefits of the Garda Síochána’s outreach at a global level.
“Large quantities of drugs have been seized, along with a significant quantity of money suspected to be proceeds of drug trafficking.
"Persons believed to operate at a significant level within the world of organised crime have been identified and arrested. A drug trafficking route has been identified and disrupted and a new method of concealing controlled substances has been identified and exposed.”