Some 40,000 ecstasy tablets and 8,000 illicit cigarettes have been recovered by customs officers.
A small cannabis grow house was also discovered in the residential address, on the south side of Cork city, this morning.
The address was tracked down after the 'Eight' brand cigarettes, which originated in China, were detected by Revenue officials in Portlaoise Mail Centre.
When a controlled delivery was carried out, officials discovered the drugs - which have an estimated street value of 400,000 euro.
Gardai were called to the scene and arrested two Chinese nationals - one male and one female - in their early 30s.
They pair were arrested taken to Bridewell Garda Station for questioning.
The cigarettes had a retail value of approximately 3,100 euro, and the potential loss to the exchequer was in the region of 2,724 euro.