Smugglers hid cocaine worth more than £1m in a consignment of protective face masks, Border Force officials said.
Officers found the 14kg haul in a Polish-registered van as it attempted to enter the UK through the Channel Tunnel.
The driver, a 34-year-old Polish national, has been arrested.
Ian Hanson, Border Force regional director, said it was “despicable” to think drug smugglers would try to exploit the coronavirus situation.
The face masks have been held pending checks by regulators, while the driver is being questioned in custody, he said.
Darren Herbert, from the National Crime Agency (NCA) Dover branch, said: “This seizure is further evidence of the way criminal networks are attempting to exploit the coronavirus outbreak to their own ends, covering this load of drugs with what would seem like vital protective equipment.”
Border Force said the van was stopped at the Channel Tunnel terminal at Coquelles, France, on Tuesday.
Officers who searched the van found 15 wrapped packages of the Class A drug.
The contents of some of the packages were tested and proved positive for cocaine.
Border Force said the investigation had been passed to the NCA.