On Saturday, customs officers of the South African Revenue Service (SARS) seized 32 pieces of rhino horn, weighing 160kg.
The rhino horns were meant to be shipped to Kuala Lumpur in Malaysia, and were wrapped in bubble wrap in a shipment declared as "live plants".
Sniffer dogs detected the rhino horn in the shipment, which was found in a cargo transit shed at the OR Tambo International Airport.
SARS says the South African Police Services' Directorate for Priority Crime Investigations (Hawks) was alerted about the shipment, and a criminal case was opened.
There have been four rhino horn busts at the airport over the past year - all bound for Malaysia. Saturday's seizure was the largest.
Previous shipments were hidden in a geyser, as well as among coffee beans, pieces of art and print cartridges.