Natalie McGarry, who was elected to represent Glasgow East in 2015 before resigning the party whip just six months later, had been due to stand trial at Glasgow Sheriff Court.
The 37-year-old had originally faced four charges relating to fraudulently claiming more than £40,000 while a senior figure in the Women for Independence campaign group, a non-party umbrella organisation.
Prosecutors today accepted her guilty plea to two charges for taking a lesser amount, while also accepting not guilty pleas to the other two.
The one-time rising SNP star embezzled the largest amount from Women for Independence in her role as treasurer of the organisation, appropriating £21,000 for her own use.
Ms McGarry transferred money raised through fundraising events into her personal bank accounts and failed to transfer charitable donations to Perth and Kinross food bank and to Positive Prison, Positive Future between April 26, 2013 and November 30, 2015.
She also used cheques drawn on the Women for Independence bank account to deposit money into her own account.
McGarry also admitted embezzling £4,661.02 in the course of her role as treasurer, secretary and convener of the Glasgow Regional Association of the SNP between April 9, 2014 and August 10, 2015.
McGarry, of Clarkston, East Renfrewshire, represented herself when she appeared at court on Wednesday.
She slumped her head on the dock as she admitted to committing the embezzlement.
McGarry was originally faced with one charge of under £33,000 but this was reduced to £21,000. The second charge, amounting to £4,661.02, was not altered.
The former politician disagreed with part of the written narrative and asked Sheriff Paul Crozier to allow her time to get legal advice.
Sheriff Crozier said: “You have been given this grace and it is in your best interest to contact your solicitor and to tell them to get in touch with the procurator fiscal.
“I will not hear the narrative or call for reports today and I will allow you one week to speak to a solicitor.”
Prosecutor Gerard Drugan asked for a hearing to confiscate money from the ex-MP, which will take place next week.
Her bail has been continued and the case was adjourned until May 1.
The outcome represents the end of a political career which at one stage looked like it could ascend to the highest levels of the Scottish Nationalist movement.
Women for Independence was established in 2012 with the aim of encouraging more female voters to back a Yes vote at the referendum eventually held two years later.
A prominent pro-independence voice on social media long before many others, McGarry was already a popular figure among the party’s members before her selection as an SNP candidate ahead of the 2015 general election, which saw the Nationalists win 56 of 59 Westminster constituencies in Scotland.
She is the daughter of veteran SNP councillor Alice McGarry, who has represented Inverkeithing for three decades, and the niece of former Scottish Parliament presiding officer Tricia Marwick.
Born and raised in Fife, she was educated at St Columba’s High School in Dunfermline before later undertaking a law degree at the University of Aberdeen.