This gives the Boxer his characteristic look. Must be in good proportion to the body and appear neither too light nor too heavy. Muzzle should be as broad and powerful as possible. The harmony of the head depends on the balance between muzzle and skull. From whichever direction the head is viewed, from front, above or sideways, the muzzle must always be in the right proportion to the
skull i.e. it must never appear too small. It should be clean, not showing any wrinkle. However, natural folds are formed in the cranial region when alerted. From root of nose, folds are always indicated running in a downward direction on both sides. The dark mask is confined to the muzzle and must be in sharp contrast to the colour of the head so that the face does not appear sombre.
- Skull: The cranial region should be as lean and angular as possible. It is slightly arched, neither too round and short, nor flat; nor should it be too broad. Occiput not too pronounced. Furrow in forehead only slightly marked, must not be too deep, especially between the eyes.
- Stop: The forehead forms a distinct stop with the bridge of nose. Bridge of nose must not be forced back into the forehead as in the Bulldog, nor should it be downfaced.
- Nose: Nose is broad and black and only slightly turned up with wide nostrils. Tip of nose is placed slightly higher than root of nose.
- Muzzle: The muzzle is powerfully developed in three dimensional volume, neither pointed nor narrow, nor short or shallow. Its appearance is influenced by: a) Shape of jaw. b) Position of canine teeth. c) Shape of lips. The canines must be placed as far apart as possible and must be of good length, making the front of the muzzle broad, almost square and forming a blunt angle with bridge of nose.
In front, the edge of the upper lip rests on the edge of the lower lip. The part of the lower jaw with lower lip curved upwards, called the chin, must not markedly protrude over upper lip, seen from front. Nor should it be hidden by the upper lip but should be well defined from front and side. The canines and incisors of the lower jaw must not be visible when mouth is closed, neither should the tongue show. Median groove in the upper lip (philtrum) is clearly visible.
- Lips: The lips complete the shape of the muzzle. The upper lip is hick and padded and fills the space formed by the undershot lower jaw; it is supported by the lower canines.
- Jaws/Teeth : The lower jaw protrudes beyond the upper jaw and is curved slightly upwards. The Boxer is undershot. The upper jaw is broad where it joins the cranial region, tapering only slightly towards the front. The teeth are strong and healthy. The incisors are as even as possible, set in a straight line. Canines wide apart and of good size.
- Cheeks : Cheeks are developed in proportion with the strong jaws without markedly bulging. They merge with the muzzle in a slight curve.
- Eyes : The dark eyes are neither too small nor protruding or deep set. Their expression conveys energy and intelligence and must not be threatening or piercing. Eye rims must be dark.
- Ears : The natural ears are of appropriate size. They are set on wide apart on highest part of skull. In repose they lie close to the cheeks and turn forward with a definite crease, especially when the dog is alert.