Chiya has long, straightened dark brown hair vaguely reminiscent of a hime cut, but with the forelocks longer and shaped differently. On the side of her head she wears a flower ornament with a ribbon. She has fair skin and green downward curving eyes.
Normally Chiya wears her work outfit, which is a dark green kimono with vertical stripes and a long white frilly apron over it.
A gentle and calming young girl, Chiya is formal and soft-spoken. She always appears to be in a light, airy mood and focuses on keeping the peace, although she can be a little air-headed. Even when she might be upset, she always keeps smiling.
Despite her ladylike behavior, Chiya has many surprising quirks one may not see at first. She finds pleasure in giving the sweets of Ama Usa An overly fancy names, such as "Red Jewel in a Snowy Field" and "Moon and Stars Reflected Upon the Sea". She also enjoys scary stories and disturbing others at times, and she dreams of becoming a samurai. She is genuinely kind, but at times she can be very teasing.
- Main article: Chiya Ujimatsu/Relationships
- "Just as the moon travels through many thousands of nights… I call it Senyatsuki! The chestnuts in the youkan represent the moon!"
- "When I look at Japanese sweets, all kinds of ideas come to me."
- "If I give up now, I would be a disgrace to all samurai! I cannot lay down my life!"
- "Since we have this chance, I'd like to hear the things you're all hiding in your hearts."
- Airo Tsurezure
- Daydream café
- Daydream café ~Gochuumon wa Chiya desu ka? ver.~
- FANCY SWEET TIME
- Furimukeba Tsuki, Iie Dango.
- Happiness Encore
- Happy Happy♪ Birthday Song
- Happy Happy♪ Birthday Song ~Chiya Ver.~
- Heart Full Moon
- Honjitsu wa Makoto ni Ra-ri-ru-rain
- Honjitsu wa Makoto ni Ra-ri-ru-rain ~Rearrange~
- Ice Cream Fantasia
- Ice Cream Fantasia ~Rearrange~
- Iroha Oshinagaki
- Kanbi Collaboration
- Kirameki Café Time ~Cover~
- Nantonaku Mirai
- Nantonaku Mirai ~Rearrange~
- Nichijou Decoration
- Nikkori Café no Mahoutsukai
- Nikkori Café no Mahoutsukai ~Rearrange~
- No Poi!
- No Poi! ~Chiya Ver.~
- Non Peace My Pace
- Ochakai Monogatari
- Otsukimi Kazoe Uta
- Pipopapo People!
- Rabbit Bibitto Show Time＊
- Sekai ga Café ni Nacchatta! (Petit Rabbit's with beans ver., Petit Rabbit's ver., Chiya ver.)
- Sentimental Button
- Singer Song Payapoya Melody (Petit Rabbit's with beans ver., Petit Rabbit's ver., Chiya ver.)
- Takarabako no Jet Coaster
- Takarabako no Jet Coaster ~Rearrange~
- Tekuteku Marching March ~Cover~
- Tenkuu Cafeteria
- Tenkuu Cafeteria ~Chiya Ver.~
- Tentakaku Otomeko Yuru Aki
- Tsukiyo ni Osatouboshi
- Waai Waai Try!
- Waai Waai Try! ~Chiya Ver.~
- Watashi to Roman Taste
- WELCOME [U-SA!] (9-Character ver., Petit Rabbit's ver., Chiya ver.)
- Yakimochi Fuumi no Chamomile
- Yume < Utsutsu → Happy Time
- Zentenkougata Irasshaimase ~Cover~
- Zutto Issho
- Chiya's voice actress also voiced Ritsu Tainaka from K-On!, Karasuma Sakura in the anime Kin-iro Mosaic and Chitanda Eru from Hyouka.
- Her name is based on "Uji matcha tea"; matcha is a finely ground powder made from green tea leaves, and Uji is a city in Kyoto prefecture which is known for its high quality green tea.
- Because of the way her name is written (千夜) it also means "A thousand nights".
- She has the uncanny ability to avoid being hit by things thrown at or near her.
- The phone Chiya uses in the anime is a "Sharp Aquos Phone SL".
- Main article: Chiya Ujimatsu/Image gallery