The Sussex Spaniel has a unique characteristic not seen in other spaniels, in that he gives "voice" or "bays" when he is on a particular game scent in a manner similar to that of the hounds. Perhaps it is because there is a lot of hound blood in his background, as can be surmised from the thickness of his skin, the leathery ears and prominent flews, all of which are characteristics of the hounds. The bell-like tones of his baying when he is on game are unique for the different game and often his master can tell which game he is hunting from the sound the dog makes.

The Sussex Spaniel is low to the ground with a compact massive body in comparison to his height. He works an area quite thoroughly and is methodical and close ranging in his technique. Often considered too slow for many hunters, he is still one of the top gun dogs where terrain is rough because of his thoroughness when quartering an area. Like most Spaniels, he will "flush" the game birds up and is also known to be a competent retriever.

The short but powerful little Spaniel is not necessarily popular in the show ring, however in the United States he is seen more in the show ring than on the hunt. He is a great companion dog and has an affectionate and winning personality, so he is also seen more as a pet dog and a therapy dog. The terrain in the United States is not nearly as rough as some of the hunting ground which is found in Great Britain which is the country of his origin and it is in rough terrain that the Sussex excels as a hunting Spaniel.

The Sussex is a particularly beautiful dog because of its distinctive reddish golden coat , often called "golden liver" because the liver color is tinged with a gold. This is the only acceptable color of the Sussex Spaniel. The coat is flat and lies close to the body, with a little wave. It is a dense double coat and because it lies close to the body with only a small amount of feathering except on the chest there is considerable resistance to burrs and snags. He is only 13-15 inches at the shoulder but the weight is 40-45 pounds. His body is long in back and quite muscular, with a deep round girth to the chest which allows for plenty of endurance for the dog. The legs, both front and back, are set wide but he is not bow-legged. The tail is always docked, the ears are long and set low and there is considerable flew on the muzzle.

This breed is affectionate and people oriented by nature, preferring human companions to canine friendships. He is a quiet and peaceable dog in the home, tolerant of children and never aggressive. Not necessarily a watch dog, he is more prone to bark or bay when he is on the hunt that he is in the home. He does well in the country or in urban areas, but of course because of his hunting instincts he must be kept in a fenced area or supervised and on a leash when outside.