The reality star and socialite will marry NBA player Kris Humphries in California on August 20, but said that she initially forgot that step-father Bruce Jenner would be there to give her away as her own father Robert Kardashian passed away in 2003.
Kardashian told Extra: "I was so nervous to walk down the aisle by myself.
"For some reason I wasn't thinking, like, 'Oh, Bruce will be there right with me', so I was thinking, 'I'm gonna fall, I'm gonna faint, oh my God, my train!'"
The 30-year-old, who chose a Vera Wang wedding gown for the ceremony, recently flew 11 hours to attend a final fitting of the garment before returning to Los Angeles.
America's Next Top Model host Tyra Banks has said that she helped advise Kardashian as she chose her dress and promised that she would look "so beautiful" as she ties the knot.