Objective To explore the value of urine C polysaccharide antigens for the diagnosis of Streptococcus pneumonia in‐fection .Methods 372 cases of patients with community‐acquired pneumonia were selected ,and their urine C polysaccharide antigens were tested by using BinaxNOW kit .Results The sensitivity and specificity of urine C polysaccharide antigens were 63 .0% and 85 .3% ,respectively .The positive rate of urine C polysaccharide antigens in patients diagnosed with Streptococcus pneumonia infec‐tion was 84 .0% ,and that in patients suspected with Streptococcus pneumonia infection was 57 .4% .Conclusion The test of urine C polysaccharide antigens can be a diagnostic adjunct for Streptococcus pneumonia infection .