To assess the extent of inappropriate hospital use in pediatric inpatients the “Pediatric Appropriateness Evaluation Protocol” was applied to 1,400 children, randomly admitted during one year in the bigest pediatric department in Greece, with a total of 6,450 days hospitalization .Results: The mean length of stay in hospital was found 4.6±4.4 days. Almost half of them (3.167 days, 49%) namely 2.26 days per child were found to be medically inappropriate. Factors significantly associated with inappropriate hospital use such as demographic and social characteristics, nature of disease, type of primary care offered to the child, process of hospital admission and medical intervantions during hospitalization were thrown into multiple regression model. It appeared that the number of tests done and the number of specialists examined the child attribute to increased inappropriate days. Children with infections disease, to divorced parents and non insured were more likely to fall into this category. Less inappropriate hospital days are associated with: the number of tests performed the day of admission: the flexibility of clinical hospital practice; the poor physical condition of the child and the admission in emergency at night .In conclusion, since social status and nature of disease are not changable better coordination of hospital diagnostic and therapeutic intervantions may reduce inappropriate hospital use and its consequences.