The reality TV star and businesswoman spoke about her results on the show, which ended on Thursday after 14 years.
The 40-year-old began a four-year legal apprenticeship with a San Francisco law firm last year, and aims to sit the California bar exam in 2022.
The first-year law exam, also known as the ‘baby bar’, is a seven-hour exam and requires 70 per cent to pass.
Kardashian is seen checking her results online and saying: “I failed! This is really annoying. Total scaled score: 463. I pretty much got the same thing. I mean, a little bit worse.”
She added: “It is what it is. I know I just have to not stress about it. There are so many stressful things going on, I just have to do better in the future.”
Kardashian, who wants to open her own law firm that will focus on sentencing and prison reform, pledged to take the exam a third time later this month.
During the finale, her sister Khloe reassured her: “You had Covid, you had your 40th birthday. You had a lot personally in your relationship. And quarantine itself. I really don’t think this time counted.”
The star is in the process of divorcing rapper Kanye West after seven years of marriage. The couple have four children together.
Kardashian opened up about the state of her marriage in the final episode and said she realised how unhappy she was after speaking to a therapist.
She told her mother Kris Jenner: “Obviously I know complete bliss is not a full reality but if I can have it more the majority of the time, that’s all I want to do.
“I just feel I’ve worked so hard in life to achieve everything that I wanted to and I lived up to my expectations and achieved 10 times more than I even thought was humanly possible, but I don’t have a life to share that with.”
Last year, Kardashian paid a visit to White House prisoners she helped to free, after she lobbied former US president Donald Trump.
She has also been outspoken in campaigning for changes to the US justice system, especially with sentencing for first-time offenders and the disproportionate effect of long sentences on ethnic minority communities.