The reality star said the label, launched on Tuesday, is inclusive and "celebrates and enhances the shape and curves of women".
But Japanese people on social media have said the trademarked brand disrespects traditional clothing.
The kimono, a loose long-sleeved robe typically tied with a sash, dates back to 15th Century Japan.
Considered the national dress of Japan, it is now mostly worn during special occasions.
"We wear kimonos to celebrate health, growth of children, engagements, marriages, graduations, at funerals. It's celebratory wear and passed on in families through the generations," one Japanese woman, Yuka Ohishi, told the BBC.
"[This] shapewear doesn't even resemble a kimono - she just chose a word that has Kim in it - there's no respect to what the garment actually means in our culture."
Kardashian West trademarked the Kimono brand last year in the US. She has also filed trademarks for "Kimono Body", "Kimono Intimates" and "Kimono World".
The underwear, designed to create smooth lines under clothing, is available in several different colours.
Kardashian West said on Twitter that there were "so many times I couldn't find a shapeware color that blended with my skin tone so we needed a solution for all of this".
Many people have taken issue with the fact she trademarked a word of huge cultural significance in Japanese culture. Others were annoyed that the traditional garment now shares the same name as an intimate wear brand.
Some have been tweeting with the hashtag #KimOhNo.
Photo Getty Images. Caption: A kimono is a traditional Japanese garment that goes back centuries