Some two tonnes of ivory and five rhino horns have been seized in Kenya's main airport inside boxes labelled as avocados to be exported to Malaysia.
The haul at Nairobi's international airport is believed to be the biggest of its kind in Kenya for several years.
Two suspects have been arrested over the seizure of the ivory, which was in 317 separate pieces.
The Kenyan Wildlife Service (KWS) says the ivory appears to be from elephants which died naturally.
It said the ivory did not have the indelible ink used to mark government-held stocks.
The KWS says there has been an increase in elephant poaching in recent years.