Kendall Jenner Describes Stalking Incident, Says 'I've Never Been So Scared In My Life'

Kendall Jenner took the stand Thursday against her alleged stalker ... where she recounted a horrifying ordeal this summer.

"I've never been so scared in my life," Kendall said in L.A. County court.

Kendall testified as a key witness in the criminal case against Shavaughn McKenzie, who faces one count of misdemeanor stalking and trespassing. Kendall looked shaken on the stand ... nervously rambling through her description of the night of Aug. 14.

She told a judge she found McKenzie sitting in front of the driveway of her Hollywood Hills home, with his head tucked between his knees.

Kendall said she drove around him and watched the gate close behind her, not thinking anyone had made it in. That is, until she saw Shavaughn in her driver side mirror.

She says she screamed, "Who are you?!" -- and McKenzie just stared at her.

Kendall then cracked her window 6 inches and shouted ... "I WANT YOU TO LEAVE!" She says he started freaking out, banging on all her windows.

Kendall says she was able to pull out of the driveway, drive down the street and call a friend.