John Katege, 32, of Tottenham, was sentenced to seven years in prison after attempting to defraud three insurers of almost £1.7m.
The City of London police said in a statement that Mr Katege claimed his friend had died in a car accident in Uganda but all the records were found to be false and she cannot be traced.
A woman who was either his friend Rose Ndadye or a woman posing as her took out three separate life insurance policies in April 2011, with Aviva, LV and Legal the General for a total value of £1.7m.
Mr Katege was the sole beneficiary of all the insurance policies.
In July 2011, the woman wrote to the insurance companies to check her cover would be valid if she travelled to Uganda in September, and to ensure the different policies did not invalidate each other.
It was confirmed this would not affect her cover.
On 18 September 2011, Mr Katege wrote to insurers to inform them that Ms Ndadye was killed in a road traffic accident in Uganda.
He submitted various documents as proof, including witness statements from people who had been present at her funeral, a police report and a post-mortem.
However, a private investigator hired by the insurance companies found that these were false.
There was no traffic accident at the time claimed, Ms Ndadye had never been a patient at the hospital the post-mortem was alleged to have taken place at, and the post mortem was a complete forgery.
City of London Police investigations in Uganda confirmed this, and interviewed witnesses who pointed to substantial evidence to show that Ms Ndadye had not died in the way that was suggested.
No trace of her alive or dead has been found in the UK or Uganda.
Mr Katege denied faking the documents, claiming that the discrepancies were a result of Ugandan incompetence. However, it was ruled his story did not add up and he was found guilty and sentenced to seven years.
Speaking after the sentencing, Det Sgt Tom Hill said: “Many criminals think life insurance fraud will be an easy way to make money.
“The Insurance Fraud Enforcement Department and insurance companies are wise to their methods and as this case shows, national borders are no object to pursuing criminals.
“His sentence should be a deterrent to those thinking of committing insurance fraud.
The Judge in his sentencing remarks praised the officer in the case for bringing such a complex case to court.