This list of spoken and sign languages beginning with the letter Y is based on data by Ethnologue, a publication of SIL International. Some languages have been bolded, to note their more wide-spread usage.
- Yaaku
- Yabaâna
- Yabarana
- Yabem
- Yaben
- Yabong
- Yace
- Yaeyama
- Yafi
- Yagaria
- Yagnobi
- Yagomi
- Yagua
- Yagwoia
- Yahadian
- Yahang
- Yahuna
- Yaka
- Yaka
- Yakaikeke
- Yakamul
- Yakan
- Yakha
- Yakima
- Yakoma
- Yakut
- Yala
- Yalahatan
- Yalarnnga
- Yale, including Kosarek, Angguruk, Ninia, and Pass Valley variants
- Yalunka
- Yámana
- Yyamap
- Yamba
- Yambes
- Yambeta
- Yamdena
- Yameo
- Yami
- Yaminahua
- Yamna
- Yamongeri
- Yamphe
- Yamphu
- Yana
- Yandruwandha
- Yanesha'
- Yangben
- Yangbye
- Yangho
- Yangkam
- Yangman
- Yango
- Yangulam
- Yankunytjatjara
- Yanomámi
- Yanomamö
- Yansi
- Yanyuwa
- Yao
- Yaouré
- Yapese
- Yapunda
- Yaqay
- Yaqui
- Yarawata
- Yareba
- Yarí
- Yarsun
- Yarumá
- Yaruro
- Yasa
- Yau
- Yau
- Yaul
- Yauma
- Yaur
- Yavitero
- Yawa
- Yawalapití
- Yawanawa
- Yawarawarga
- Yaweyuha
- Yawiyo
- Yawuru
- Yazgulyam
- Yei
- Yekhee
- Yekora
- Yela
- Yele
- Yelmek
- Yelogu
- Yemba
- Yemsa
- Yendang
- Yeni
- Yeniche
- Yerakai
- Yeretuar
- Yerong
- Yerukula
- Yeskwa
- Yessan-mayo
- Yetfa
- Yevanic
- Yeyi
- Yi, including the central, guizhou, sichuan, southeastern, western, and yunnan dialects.
- Yiddish, including Eastern and Western variants
- Yidgha
- Yidiny
- Yil
- Yimas
- Yinchia
- Yindjibarndi
- Yindjilandji
- Yine
- Yinggarda
- Yinglish, not to be confused with English
- Yir yoront
- Yis
- Yiwom
- Yoba
- Yogad
- Yoidik
- Yoke
- Yokuts
- Yombe
- Yonaguni
- Yong
- Yongkom
- Yopno
- Yora
- Yoron
- Yoruba
- Yos
- Yoy
- Yuaga
- Yubanakor
- Yuchi
- Yucuna
- Yugambal
- Yugh
- Yugur, East and West variants
- Yuhup
- Yukaghir, Northern and Southern variants
- Yuki
- Yukpa
- Yukuben
- Yulu
- Yupik, including Central, Central Siberian, Naukan, Pacific Gulf, and Sirenik variants
- Yuqui
- Yuracare
- Yurok
- Yuruti
- Yuwana
Non-Spoken Languages
