A mid vowel (or a true-mid vowel) is any in a class of vowel sounds used in some spoken languages. The defining characteristic of a mid vowel is that the tongue is positioned midway between an open vowel and a close vowel.

Other names for a mid vowel are lowered close-mid vowel and raised open-mid vowel, though the former phrase may also be used to describe a vowel that is as low as open-mid; likewise, the latter phrase may also be used to describe a vowel that is as high as close-mid.

The only mid vowel with a dedicated symbol in the International Phonetic Alphabet is the mid central vowel with ambiguous rounding [ə].

The IPA divides the vowel space into thirds, with the close-mid vowels such as [e] or [o] and the open-mid vowels such as [ɛ] or [ɔ] equidistant in formant space between open [a] or [ɒ] and close [i] or [u]. Thus a true mid front unrounded vowel can be transcribed as either a lowered ⟨e̞⟩ (with a lowering diacritic) or as a raised ⟨ɛ̝⟩ (with a raising diacritic). Typical truly mid vowels are thus:

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