Senator Ike Ekweremadu, 60, and his wife Beatrice, 56, wanted the organ for their 25-year-old daughter Sonia, the couple’s trial at the Old Bailey heard.
The pair and and Dr Obinna Obeta, 50, were convicted previously of conspiring to exploit the man for his kidney.
It is said to be the first such case under modern slavery laws.
Ike Ekweremadu, who was described by the judge as the “driving force throughout”, was sentenced to nine years and eight months in prison.
Dr Obeta was sentenced to 10 years after the judge found he had targeted the potential donor who was young, poor and vulnerable.
Beatrice Ekweremadu was jailed for four years and six months due to her more limited involvement.
Their victim, a poor street trader in Lagos, was brought to the UK to provide a kidney for the Ekweremadus’ daughter.
He fled in fear of his life and walked into a police station exactly a year ago to report what had happened after the Royal Free Hospital called a halt on the private £80,000 procedure.
During a televised sentence hearing, Mr Justice Johnson recognised Ike Ekweremadu’s “substantial fall from grace”.
He described the politician as someone of high office with multiple properties, domestic staff, maids, chefs and drivers compared with the victim, who could not afford a £25 ticket to travel to Abuja.
Obeta, he said, had lied to doctors and falsely claimed the young potential donor was a cousin of the senator’s daughter who urgently needed a transplant.
The three had left the potential donor facing a “substantial and long term impact on his daily life”, he said.
“People-trafficking across international borders for the harvesting of human organs is a form of slavery,” the judge added.
In a victim personal statement, the 21-year-old Nigerian market trader, who cannot be named for legal reasons, told the court he used to “pray every day” to be given the opportunity to come to the UK to work or study.
