Ibrahim Moro, 33, from Bromley, and Rebecca Patrick, 32, from Croydon, used dating sites to convince old people that they were in the loving relationships they desperately craved.
One elderly Australian man who believed he was in a relationship with Patrick was initially asked for small amounts to buy her clothes for the winter.
But Patrick then told him she was entitled to 78kg of gold in Ghana and had to pay for it to be released.
She told the elderly man that when it was released she would move to Australia and live with him.
The man transferred almost £138,000 to the fraudsters.
The Australian man died before Moro and Patrick were sentenced.
They persuaded her to send £18,000 by telling her they were having insurance problems.
Another woman was tricked into sending money to a man she thought was a German widower living in Ascot who was buying gold, silver and diamonds for clients.
The woman told officers that although she had never met the man, she regarded him as a “close friend and confidant”.
In March 2016 she was told he was overseas and had bought some precious stones, but was unable to leave the country until he had paid taxes on them.
She was asked to pay the amount and was told “if you don’t loan me the money, that means you don’t care about me”.
In the end she sent £2,500, which went straight into Patrick’s account.
Investigators from the National Crime Agency linked Moro to an email account used to defraud one victim.
They also found that Moro and Patrick provided their victims the same address that they had given to their banking providers.
But the pair were convicted and on Tuesday (January) Moro was sentenced to five-and-a-half years in prison while Patrick got an 18 month suspended sentence.
The couple denied the offence – Moro claiming the money was from a clothing business while Patrick claimed she had given Moro access to her accounts.
NCA Operations Manager Paul Boniface said: “These defendants exploited the vulnerability of their victims, selling them a relationship story they desperately wanted to believe.
“The Australian victim that Moro and Patrick so cruelly manipulated has sadly died before seeing these defendants sentenced.
“Romance fraud affects victims not only financially but also emotionally – many victims find it too painful to contemplate they have been scammed by someone they thought they could trust.
“Criminals may pretend to be a trusted person when they message but if something seems suspicious or unexpected, such as requests for money, listen to your doubts and do not send funds.”
