Wolf teeth are small, peg-like horse teeth, which sit just in front of (or rostral to) the first cheek teeth of horses and other equids. They are vestigial first premolars, and the first cheek tooth is referred to as the second premolar even when wolf teeth are not present. Torbjörn Lundström in Sweden reported that about 45-50% of 25000 horses had wolf teeth. They are much less common in the mandible (lower jaw) than the maxilla (upper jaw) although mandibular wolf teeth are found very occasionally.

They do not have any deciduous precursors, but they may themselves be deciduous, as it is believed that they are often shed when the deciduous 2nd premolar is shed at around two and a half years of age. They may also be knocked out by the bit if particularly loose, and can certainly be extracted accidentally, either partially or whole, when routine equine dentistry is performed.

In size they are extremely variable from being small pegs only 3 mm in diameter to having roots up to 2 cm long. In a small number of cases they may be "molarized" with a distinct irregular rim of enamel. It is impossible to gauge the size of the root from an examination of the crown, except to say that if the crown is mobile it is very unlikely that there is a large intact root.

There is dispute as to the average time of eruption with different authors suggesting different times. All authors who have performed any type of rigorous study suggest that they erupt between birth and 18 months although most say 6–9 months.

Where there are two wolf teeth next to each other, it is very likely that one is a fragment of the deciduous 2nd premolar.