2023 Keio Challenger

The 2023 Keio Challenger was a professional tennis tournament played on hard courts. It was the 16th (men's) and 6th (women's) editions of the tournament and part of the 2023 ATP Challenger Tour and the 2023 ITF Women's World Tennis Tour. It took place in Yokohama, Japan between 20 November and 3 December 2023.

2023 Keio Challenger
Date	20 – 26 November (men's) 27 November – 3 December (women's)
Edition	16th (men's) 6th (women's)
Category	ATP Challenger Tour ITF Women's World Tennis Tour
Surface	Hard
Location	Yokohama, Japan
Champions
Men's singles
Yosuke Watanuki
Women's singles
Aliona Falei
Men's doubles
Filip Bergevi / Mick Veldheer
Women's doubles
Liang En-shuo / Tang Qianhui

Men's singles main-draw entrants

Seeds

Country	Player	Rank1	Seed
JPN	Yosuke Watanuki	81	1
AUT	Jurij Rodionov	107	2
USA	Michael Mmoh	109	3
AUS	James Duckworth	113	4
USA	Maxime Cressy	127	5
ITA	Luca Nardi	128	6
AUS	Marc Polmans	158	7
SUI	Leandro Riedi	160	8

• ¹ Rankings are as of 13 November 2023.

Other entrants

The following players received wildcards into the singles main draw:

• Masamichi Imamura
• Rio Noguchi
• Rei Sakamoto

The following player received entry into the singles main draw as an alternate:

• Altuğ Çelikbilek

The following players received entry from the qualifying draw:

• August Holmgren
• Kalin Ivanovski
• Omar Jasika
• Naoki Nakagawa
• Colin Sinclair
• Yasutaka Uchiyama

The following players received entry as lucky losers:

• Chung Yun-seong
• Mathys Erhard
• Giovanni Fonio

Champions

Men's singles

Main article: 2023 Keio Challenger – Men's singles

• Yosuke Watanuki def. Yuta Shimizu 7–6^(7–5), 6–4.

Women's singles

• Aliona Falei def. Ayano Shimizu, 6–3, 7–5

Men's doubles

Main article: 2023 Keio Challenger – Men's doubles

• Filip Bergevi / Mick Veldheer def. Ray Ho / Calum Puttergill 2–6, 7–5, [11–9].

Women's doubles

• Liang En-shuo / Tang Qianhui def. Aoi Ito / Natsumi Kawaguchi, Walkover