Fever is the most common medical condition in pediatric age, and it is also one of the most anxious and worrying conditions for parents. Most of the most common causes of pediatric fever are infectious diseases, of course there are some rheumatic immune diseases, but the following are the most common possible causes and diseases that cause pediatric fever: 1. runny nose, nasal congestion, light cough, cold. 2.Sore throat, pharyngitis, tonsillitis. 3, cough, shortness of breath, dyspnea, pneumonia. 4.Ear canal running water, emotional instability, otitis media. 5.Red and swollen gums, oral herpes or ulcers, salivation – stomatitis. 6.Parotid swelling and pain, mumps. 7.Vomiting, bulging fontanelle, seizure, unconsciousness-encephalitis, meningitis. 8.Exhaustion, heat stroke while having high fever in hot places. 9.Urinary frequency, urinary urgency, urinary pain, hematuria, urinary tract infection. 10.Fever accompanied by seizures, fever convulsions. 11, Fever with rash, measles, rubella, scarlet fever, septicemia, Kawasaki’s disease, etc. 12, . Fever with joint swelling and pain-rheumatic, rheumatoid and other immune diseases.