This article describes two- and three-letter combinations (so-called digraphs and trigraphs) used for the Mongolian language when written in the Mongolian script.

Mongolian script multigraphs
The Mongolian script
Mongolian vowels
ᠠ​ a ᠡ​ e ᠢ​ i ᠣ​ o ᠤ​ u ᠥ​ ö ᠦ​ ü ᠧ​ (ē)
Mongolian consonants
ᠨ​ n ᠩ​ ng ᠪ​ b ᠫ​ (p) ᠬ​ q/k ᠭ​ γ/g ᠮ​ m ᠯ​ l ᠰ​ s ᠱ​ š ᠲ​ t ᠳ​ d ᠴ​ č ᠵ​ ǰ ᠶ​ y ᠷ​ r ᠸ​ (w)
Foreign consonants
Mongolian script multigraphs
v t e

Vowel and consonant combinations

The intervocalic letters γ/g, and y has in some combinations come to help form long vowels, namely:^{[1]: 36–37}

• Long a with: aγa, iγa, iya.
• Long e with: ege, ige, iye.
• Long i with: igi.
• Long o with: oγa, oγo, uγa.
• Long u with: aγu, iγu, uγu.
• Long ö with: öge, üge.
• Long ü with: egü, igü, ügü.

Sometimes intervocalic b and m is silent: as in ᠳᠡᠪᠡᠯ debel (дээл deel) 'robe, garment' or ᠬᠦᠮᠦᠨ kümün (хүн khün) 'human, person; man'.^{[2]: 64 [3]}

Vowel combinations

Doubled vowels[1]: 10, 30 [4]: 59
ii	oo	uu	üü	Transliteration[note 1]
ī	ŏ	ū	ǖ	Pronunciation
—	—	ᠤᠤ⟨?⟩ ⟨⟩[a]		Alone
		ᠣᠣ[b]	—
		ᠤᠤ‍	ᠦᠦ‍[c]	Initial
‍ᠢᠢ‍	‍ᠣᠣ‍[d]		(‍ᠦ᠋ᠦ‍)[e]	Medial
—	—	‍ᠤᠤ[f]		Final

• The doubled vowels ii, uu, and üü mark these out as long. Doubled oo is instead both used in a few words to mark the vowel as short, and to distinguish it from u.^[1]: 30

• Most of the i's of these diphthongs derive from an earlier yi, but is no longer recognized as such. The yi origin can for instance be seen in the two long teeth of ᠰᠠᠶᠢᠨ^⟨?⟩ sayin 'good'. These has become a pair of short and long teeth (᠊‍ᠢ᠋‍) in recent manuscripts. The diphthongs only appears with the single form of i, as in ᠳᠠᠯᠠᠢ dalai̯ 'sea', at the end of words.^{[1]: 10, 31 [4]: 9, 58}

Diphthongs, continued[1]: 11, 31–32
au	eü	u‑a	uu‑a	Transliteration
aū	eǖ	uă/uā	ūā?	Pronunciation
ᠠᠤ‍	—	—	—	Initial
‍ᠠᠤ‍				Medial
—		‍ᠤ᠎ᠠ⟨?⟩ ⟨⟩[k]	‍ᠤᠤ᠎ᠠ⟨?⟩	Final