Chumlong Lemthongthai pleaded guilty to 59 offences against the South African Customs and Excise Act and environmental legislation in relation to the killing of around 26 rhinos in bogus trophy hunts.
Five other co accused were released - the charges against them dropped after Chumlong claimed that he alone knew the rhino horns were being exported for profit.
Chumlong paid Thai commercial sex workers to pose as hunters and obtain export certificates for horns, which were in fact taken from rhinos killed by professional hunters.
The prosecution was brought by the South African Revenue Service and South African Police Service, and has been supported by a parallel enquiry by Thai authorities.
FREELAND (an international organisation dedicated to tackling wildlife trafficking and human slavery) investigators have been assisting Thai authorities since February 2011 when 6 rhino horns, declared as “hunting trophies” for three Thai females, were discovered at Bangkok Suvarnabhumi Airport.
“Our information suggests that Chumlong was guilty, no doubt about it,” said Steven Galster, Director of FREELAND.
"South African authorities have done a great service to Southeast Asia for putting a major criminal who was threatening wildlife in this region too behind bars.
"However, this one man was not the mastermind, nor do we believe his South African and other Thai co defendants were innocent. We support a continuation of this investigation."