The former X Factor judge is said to have wept in the courtroom as the judge delivered his verdict on Wednesday, 14 January following a three-day hearing.
Tulisa, 26, was found guilty last year of hitting Vas – real name Savvas Morgan – while attending the celebrity-packed V Festival in Chelmsford, Essex in August 2013.
She had vowed to appeal, declaring: "I did not assault Vas J. Morgan and I'm outraged at this decision. I will be appealing it. There are a number of high-profile witnesses who were there and know what happened. I urge them to come forward and tell the truth at the appeal. I am determined to clear my name as I have already done once this week. I repeat - I did not assault Vas J Morgan. I am innocent."
During her appeal, the N-Dubz singer had claimed Vas had a "strange obsession" with her and "vendetta" against her. She also accused of him of calling her derogatory names and making comments about her mentally-ill mother.
However, the judge at Snaresbrook Crown Court found that Tulisa had a "lack of self control" which led to the incident, although he added he had "sympathy" for Tulisa.
"We find she was not calm, this was a lack of self-control - the reasons, we understand - and for a brief moment, we find that she did strike Mr Morgan, before very speedily the incident was brought to an end," said Judge David Radford.
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