Kris, 60, presented the model with the luxury vehicle outside Los Angeles' hotspot Delilah's, the second venue, where Kardashian-Jenner clan visited to celebrate Kendall's birthday, reported Us weekly.
Kendall looked stunning in a glittery silver short dress.
"Kris gave Kendall a Rolls-Royce! Kendall was shocked! Totally surprised and delighted" a source said.
"The Keeping Up with the Kardashians" star's mother also took to Instagram to wish her- "Happy Birthday".
"Happy 21st birthday my sweet angel, @kendalljenner!!! You are so beautiful inside and out. Thank you for being YOU and for blessing us with your kindness, your adorable sense of humour and your love.
Khloe Kardashian also tweeted for her half sister, "Happy birthday @kendalljenner !! My baby sis is all grown up yassssss!"
However, Kim Kardashian remained silent on her social media about her sister's birthday, but she reportedly came to attend the family dinner.