Mr Griffiths, who was criticised during the MPs' expenses scandal when he claimed for a 3,600 plasma television, is eligible for the cash payment to help him "adjust" to life outside Parliament. Half of the payment is tax-free.
The Edinburgh MP is also eligible for a winding-up allowance designed to help with the expenses of running down a constituency office.
But news of the payment and Mr Griffiths's new job have been decried as "unacceptable" by campaigners in the wake of simmering public anger surrounding the MPs' expenses scandal.
Martin Bell, the former MP who has written a book on the expenses saga, said: "It is quite reasonable for an MP who leaves at the behest of an election defeat to get this payment. But I would have thought, if they have already lined up a job before leaving office, they should not be paid the money because it has come from the taxpayer."
It was widely predicted that Mr Griffiths would have struggled to retain his Edinburgh South seat following a sex scandal in 2008. The former minister allegedly had an intimate encounter with a brunette in his Westminster office.
The 54-year-old, who has been married for 30 years, later apologised for engaging in sexual activity in his House of Commons office. He said he was ashamed of his actions, which he said fell below acceptable standards.
The Scotsman revealed yesterday that Mr Griffiths told party members in his constituency that he would not be standing for re-election and would instead take up a job with an "international educational institution".
That body is now understood to be the London International College (LIC), an independent not-for-profit organisation, founded in 1974 and offering undergraduate and postgraduate degree courses to foreign students on programmes accredited by Sunderland University.
Mr Griffiths already acts as the chairman of the board of trustees for LIC, fuelling speculation he was set to accept a directorship. A spokesman for the LIC would not confirm the appointment, but said: "Why don't you pose that question to Mr Griffiths? It is best if he answers that."
The Scotsman attempted to put the question to Mr Griffiths, but he could not be contacted.
Earlier, he denied the fallout from the sex scandal had led to his decision, saying: "I am confident I would have held the seat had I stayed on, and am confident that the Labour Party will still hold the seat. It was a hard decision to take, but it's a very exciting challenge. It's a field I have specialised in. The offer came out of the blue in the past few days and once I checked out its authenticity, it was straightforward."
Under Commons rules, MPs losing their seat at elections are entitled to the "parachute" payment to help them "adjust" to life outside the Commons. The "golden goodbyes" are still payable to MPs standing down of their own volition, even if they have been found to have breached expenses rules or lined up another job prior to leaving office.
A Commons spokesman confirmed that, as long as he stood down at the time of an election, Mr Griffiths would be entitled to the resettlement grant. His age and length of service mean he will receive 92 per cent of his MP's salary of more than 64,000, leaving him with a 59,500 lump sum, of which the first 30,000 will be tax-free.
Ironically, it is widely expected that the terms of such grants will be amended after the election as a result of reforms prompted by the expenses scandal.
Currently, however, rules laid down in the Commons' "Green Book" state: "If you leave the House at a general election, you will normally receive a resettlement grant of between 50 per cent and 100 per cent of salary, depending on your age and length of service at the date of Dissolution."
In addition, when Mr Griffiths chooses to close his constituency office, the winding-up allowance will allow him to pay his staff statutory redundancy payments, as well bonus payments of up to 15 per cent of their salary.
Mark Wallace, of the TaxPayers' Alliance, said his organisation was lobbying for the Commons resettlement grant to be scrapped: "It is unacceptable to give MPs who choose to leave the Commons, or are thrown out by the people, these massive sums of money.
"MPs are well rewarded while they are in office and get a very generous pension. These payments make it a triple whammy. For ordinary people struggling to make ends meet in the recession, this is a real slap in the face."
But there was little appetite for comment from opposition politicians, mindful that the resettlement grant would be paid to politicians of all parties standing down at the next election.
An SNP spokeswoman said: "It comes as no surprise that Nigel Griffiths has added his name to the list of scandal-hit Labour MPs who would rather take their resettlement packages than stare defeat in the face."
Meanwhile, his decision has provoked anger among some local party members, who questioned the timing of the announcement months before a general election must be held.
One Labour Party insider said: "This decision is just typical of Nigel. That is why he will leave no legacy in South Edinburgh. He has put the party in a very difficult position by making his entire campaign centre on his personality. He was a policy-free zone. If we lose Edinburgh South, everyone will know who to blame: Nigel Griffiths."
Another local member added: "He has obviously been working on this for some time, and has now dumped the local party in it before an election."
Fellow Labour MPs spoke of their shock at the decision. Edinburgh MP Gavin Strang said it had come as "a bolt out of the blue".
"I am saddened because Nigel Griffiths was an exceptionally hard-working MP," he said. "There is no doubt he is very well respected and has worked very hard in that constituency."
Jim Sheridan, Labour MP for Paisley and Renfrewshire North, said: "Nigel has always been a campaigner for the party. From a personal point of view, I am disappointed he is standing down because he was a very good constituent MP."
The local Labour Party insisted no successor had yet been identified to fight in his place, but it is understood local councillor Ian Murray is likely to stand.
POSSIBLE LABOUR RUNNERS
A CURRENT Edinburgh City councillor, Mr Murray represents Labour in the Liberton and Gilmerton ward and was linked with the vacant Labour candidacy in Livingston created when Jim Devine stepped down.
That spot has now been filled, but Mr Murray, who runs an events management company, said he was considering his options.
"At this stage I haven't made any decision as yet – but I will have to think long and hard before I put my name forward. Lots of people have been phoning me to encourage me to do so," he said.
THE former leader of Edinburgh City Council now runs the Scottish arm of PR and lobbying consultancy PPS. Before that, he stood as the Labour candidate in the Edinburgh South constituency in the 2007 Scottish Parliamentary elections, being defeated by Mike Pringle of the Liberal Democrats.
Yesterday, Mr Anderson played down suggestions he could stand: "I have had a number of approaches but, as I have always made clear, I am not interested in standing for Westminster."
LABOUR is keen to put up women for winnable seats as part of an effort to even out the number of male and female MPs in Westminster.
Ms Boyack is well regarded in the Labour Party, even though she has publicly disagreed with the leadership on issues such as nuclear power.
Her constituency, Edinburgh Central, is also very close to Nigel Griffiths' Edinburgh South and she may want to follow some of her fellow MSPs who have recently been nominated for Westminster seats.
A FORMER member of the Scottish Parliament for the Edinburgh South constituency, Mr MacKay was deputy justice minister before being voted out in 2003.
He is also a former Edinburgh City councillor and finance convener and now runs public policy consultancy MacKay Hannah.
Despite his obvious credentials, Mr MacKay ruled himself out of contention yesterday, telling The Scotsman: "I will not be putting my name forward, but it's possible one or more of the Labour councillors will put their name forward."
Faint hearts and lost confidence as members charge for the exit
Affluent battleground balanced on knife-edge majority of 405