Officers from the Garda National Drugs Unit discovered the drugs after they stopped a truck and a car at a business park in Swords this afternoon.
Two men aged 41 and 44 were arrested at the scene and are being questioned in Swords and Malahide Garda stations.
This latest seizure is the result of an ongoing investigation by the garda national drugs unit into the activities of a man known to them as a significant drug dealer.
The 44-year-old had been released from prison in the last 12 months after serving more than seven years for drugs offences.
A northern-registered truck and a car were stopped at around 12.30pm this afternoon.
49kg of cannabis pollen, comprised of the buds of the plant, and another 10kg of cannabis herb were found in the back of the truck.
The two men can be questioned for up to a week.
Gardaí believe the drugs were being brought in by a criminal gang with links to drug traffickers in Northern Ireland.
