Limavady lorry driver, Stephen McLaughlin and Martin McGlinchey, from Dungannon, were convicted of conspiracy to facilitate illegal entry into the UK following a re-trial in London on Thursday.
At Basildon Crown Court McLaughlin, of Rose Park, Limavady, was jailed for eight years and McGlinchey, of Derryloughlan Road, Dungannon, for nine years.
The Afghan Sikhs, including 15 children, were discovered on August 16 2014 after port workers at Tilbury Docks in Essex heard banging noises and cries for help.
When the container was opened, the asylum seekers were found crammed on top of plastic barrels full of liquid, with condensation pouring from the ceiling.
Among them was Meet Singh Kapoor, a 40-year-old who died during the overnight P&O ferry crossing from Zeebrugge, Belgium. A post-mortem examination found he died of natural causes.
Police said his family, who were travelling with him, watched him die and were powerless to seek medical help in the dark container that had just two air holes.
There were no toilets and the children were sick in carrier bags. At one point, the air holes were closed as other containers were loaded next to theirs, police revealed.
The jury was told the asylum seekers were the “human cargo” of a “sophisticated international organisation” of people smugglers.
The court heard the asylum seekers had paid thousands of pounds to travel to the UK to escape persecution from radical Muslims in Afghanistan.
The men told how they paid around £28,000 per family for the crossing, raising the cash by selling their businesses, stock and family jewellery.
McLaughlin and McGlinchey were part of a team responsible for arranging the transport logistics of the people smuggling operation.
The pair organised for the container to be sent from Dover, Kent, to France so it could be picked up before being loaded with asylum seekers on a Belgian industrial estate.
A third man, Taha Sharif, 39, of High Cross Road, Tottenham, north London, was found guilty of the same offence following a trial last July. He will be sentenced on June 23.
Detective Chief Inspector Martin Pasmore, of Essex Police, said afterwards: “Vulnerable people seeking help were treated in an appalling way at the hands of these greedy criminals, which prevented any prospect of medical help for Mr Kapoor.
“My thoughts remain with his wife, children, family and friends, and the other surviving asylum seekers who endured such distressing and shocking conditions.