Barbara Ugolor was sentenced to four-and-a-half years in prison after she knifed the busker in broad daylight during rush hour on October 25 2017.
The 46-year-old, of Iffley Road, Hammersmith, was sat in the busker's designated spot outside the Underground station and refused to move when he asked.
Instead, she lunged towards the 46-year-old victim and stabbed him in the cheek.
Ugolor denied a charge of grievous bodily harm with intent but was found guilty by a jury. She was sentenced last Friday (April 20).
The busker was rushed to nearby Guys Hospital at around 5.30pm, just after the attack, but his injuries were non life-threating and he was later discharged.
Detective Constable James Inquieti said: “This was a completely unacceptable and vicious attack which is reflected in the severity of the sentence handed to Ugolor.
“Thankfully, the man sustained non-life threatening injuries and was able to return home after immediate medical attention at Guys Hospital.
“Ugolor has now been brought to justice and is paying the price for this reckless act of violence.”