Simon Buckden today admitted six charges of fraud midway through his trial at Leeds Crown Court.
Buckden, 44, had previously denied all charges.
The jury had heard Buckden making false claims to have cancer.
He claimed to have served with the SAS and was invited to take part in the 2012 Olympic torch relay through Leeds after building up a reputation as a heroic fundraiser and campaigner.
Leeds Crown Court heard people provided money and practical help after hearing of his cancer diagnosis and being inspired by story.
Buckden changed his pleas to guilty after the court received a joint report from a psychologist and a psychiatrist.
Judge Christopher Batty discharged the jury and told Buckden he will be sentenced on Monday.
The total value of the offending is £7,700.
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