Due to the size of the breed being modified to become a short nosed dog with a very rounded skull similar to the popular pug; there are some common health problems that King Charles spaniels suffer from which include:
* Mitral valve disease which is a condition that causes degeneration of the mitral heart valve that can be fatal for most dogs. All cavaliers should be screened for heart murmurs once a year beginning at age 1 year due to the commonness of the disease in the breed as it is the leading cause of death of cavalier King Charles spaniels, as it is a hereditary disease passed through generations from excessive breeding.
* Patellar luxation-kneecap dislocation
* Cataracts eye condition which is when the eye's lens usually becomes
* Mitral valve disease which is a condition that causes degeneration of the mitral heart valve that can be fatal for most dogs. All cavaliers should be screened for heart murmurs once a year beginning at age 1 year due to the commonness of the disease in the breed as it is the leading cause of death of cavalier King Charles spaniels, as it is a hereditary disease passed through generations from excessive breeding.
* Patellar luxation-kneecap dislocation
* Cataracts eye condition which is when the eye's lens usually becomes