There are several congenital diseases and conditions that French Bulldogs are prone to, although they are still considered the healthiest of the Bull Breeds. Frenchies can suffer from Von Willebrand's Disease (VWD), a bleeding syndrome similar to to Haemophilia in humans which can impede their clotting. In conjunction to this, French Bulldogs may also suffer from thyroid condition. Many breeders follow a program of testing younger dogs for VWD, and only testing for thyroid at that time if the VWD factor is low. In this program, the breeder tests thyroid again just prior to using the dog for breeding. Other breeders test both VWD and Thyroid at the same time.

As a result of the rather cramped conditions that a Frenchie's flat face creates, one of the most common defects in French Bulldogs is elongated soft palate or cleft palate. Puppies affected with Cleft palate are generally put down at birth, as it is generally considered to be an almost impossible condition to correct. Elongated soft palate can manifest as anything from a mild condition causing labored breathing to severe condition that can cause the affected dog to pass out from moderate exercise. One of the most disgusting possibilities in a dog affected with elongated palate is passive regurgitation, in which the affected dog vomits up food or phlegm after eating or exercise. It is generally advisable to ask breeders if either parent has elongated soft palate, or has ever been operated on for the condition.

Another result of the compacted air way of the French Bulldog is their inability to effectively regulate temperature. While a regular canine may suffer to some degree from the heat, to a Frenchie it may be lethal. It is imperative that they be protected from temperature extremes at all times, and that they always have access to fresh water and shade.

French Bulldogs can also suffer from an assortment of back and spinal diseases, most of which are probably related to the fact that they were selectively chosen from the dwarf examples of the Bulldog Breed. Some breeders feel that only dogs that have been X-rayed and checked for spinal anomalies should be bred from, but this is a difficult position to take sides on. While it is true that no dog affected with a spinal disease should be bred from , there is a great deal of variance in the appearance of a French Bulldog's spine as compared to, for example, a Labrador Retriever. If possible, such decisions should be left to either a Vet or breeder who has seen quite a few Bulldog Breed Spinal Xrays, to avoid eliminating dogs unnecessarily.