Abstract： Objective To study the clinical features of invasive pneumococcus disease (IPD) with resistance to antimicrobial agents in children,and to improve the diagnosis and treatment of this disease.Methods The clinical data from 21 IPD patients younger than 13 years old were collected from January 2008 through December 2010 in Pediatric Intensive Care Unit in Beijing Children's Hospital for retrospective analysis. Specimens of blood,pleural effusion,cerebrospinal fluid and soft tissue aspirated were collected from these children,and 23 strains of streptococcus pneumonia (SP) were cultured,isolated and confirmed,and the antibiotics susceptibility to penicillin and other antibiotics of these strains were assayed.Results Among the 21 IPD children,the ratio of male to female was 0.9∶1,and the age was 5 months to 13 years,with 61.9％ of them under 2 years.Of them,12 patients (57.1％ ) had purulent pleurisy,and 1 (4.8％ )patient had an underlying disease diagnosed to be X - linked agammaglobulinemia (XLA).There was no seasonal difference in the occurrence rate of this disease. Eight (38.1％) patients were cured,11(52.4％ ) were improved,while 2 (9.5％ ) patients not improved without death.There was no statistically significant difference in the annual detection rate of invasive SP (x2 =3.711,P =0.156).The incidences of penicillin-intermediate susceptibility SP (PISP) and penicillin-resistant SP (PRSP) were 47.8％ and 26.1％ respectively.The rate of resistance to multiple antibiotics was 91.3％.Conclusions Children aged less than 5 years,especially younger than 2 years,are prone to IPD,and purulent pleurisy and septicemia are often seen in this disease. Some patients had the underlying diseases.The complications included hemophagocytic syndrome,acute respiratory distress syndrome,septic shock,bronchial pleural fistula and so on.The multidrug resistance rate was 91.3％.It is important to put great emphasis on the monitoring antibiotics resistance to invasive pneumococcal disease.