Dogs vomiting yellow water may be caused by gastrointestinal diseases, internal parasites, improper diet, viral infections, etc. It is best to take your dog to the hospital for examination to rule out the possibility of infectious diseases. Dogs' gastrointestinal tracts are relatively sensitive, so do not feed them random food, especially food that is difficult to digest or highly irritating. Regularly deworm the dog's body and occasionally feed it some probiotics to help regulate the gastrointestinal tract.