The individualized, retrospective study of 14 children with SLE (4-16 years) pointed out a series of clinical and age dependent evolutive characteristics. Below the age of 10 years old (lot 1:2 boys and 4 girls), SLE started as a prolonged fever syndrome (5-16 weeks) in the majority of cases; for 2 children the severe poliarthritis resistant to the AINS therapy is associated with the durable absence of the antinuclear seric antibody (ANA). For the same age group a high frequency of neurological manifestations (5/6 cases) was noticed. After the age of 10 years old (lot II: 8 girls) the symptoms incidence at debut is close to the one of the adult, the cutanat and renal manifestations in evolution were dominant (7/8 cases). The 7 months absence of ANA characterises a case that started with hepatomegaly, severe neurological and physiological manifestations and microscopic hematuria. The follow-up lasted until the age of 16 years old; the patients were clinically tested for severe renal complication. The correct application of the classical criteria of diagnostic (ARA, 1982), and in the last few years the application of the ponderat score (Mayer, 1998), allows us to establish an early diagnostic and a rapid evaluation of a relapse, therefore influencing the treatment.