This large and leggy hound is well known outside of France, its country of origin, even though there are few examples of the breed elsewhere except in the dog shows of Europe and Great Britain. This breed is often termed the "King of Hounds" because of its remarkable stature and great beauty. Furthermore this hound is noted for its tenacity on the hunt and its deep and melodious voice. The Grand Bleu is tall but proportionate in size and is marked with black patches on a mottled roan background with tan. The black patches on the head must always cover both ears and the sides of the head and the entire body is so mottled as to leave the impression of blue roan coloration.

There are four dogs which come from the region of Gascogne in France, all have the Gascogne designation in their name; they are believed to be among the purest of the hound dogs since they are directly descended from the original Phoenician hounds crossed with the Gallic scenting hounds. The Grand Bleu lays claim to being the direct descendant of the now extinct Chien Courant, a hound of legendary strength and size. The Grand Bleu was known to bring down wolves in the early days, now it is a hound that is used primarily for hunting deer and wild boar.

The Grand Bleu is nearly as tall as the larger Giant breeds such as the Newfoundland or the Great Pyr but does not carry nearly the weight. It can be 29-29 inches at the shoulder but the weight is that of the Labrador retriever or other large dogs weighing about 80 pounds. This gives him a lean appearance but this is deceiving for he is a well built dog and has considerable endurance for the hunt if he is conditioned. These hounds have a slow gait and a methodical approach to the hunt, which is a useful trait in the hot climate of southern France, where everything seems to move at a relaxed pace. This is a typical hound in manner and affability, being gentle and accepting of people and quite comfortable as a house dog or a kennel dog. His greatest joy is to go on the hunt however and since he is independent as most hounds are he needs to be in a fenced area if kept outside.

This is a hound that is quite strong physically. His natural playfulness as a puppy and his large size can make him a real nuisance to have in a household until he learns to be mannerly. Because of his large size he needs early training in obedience as do all large dogs. Generally the Bleu De Gascogne is little used as a hound today and he is more of a dog that is shown . He is registered by both the F.C.I. and the Kennel Club of Great Britain but is not recognized by the A.K.C. The Grand Bleu de Gascogne has become a breed that is admired as a home or farm companion of great gentleness and affection. Yet the dog has a voice that will intimidate the strangers on the property and consequently he makes a reliable watchdog also.