Objective To explore the value of combined detection of serum testosterone (T) with dehydroepiandrosterone sulfate (DHEA-S) in diagnosis of polycystic ovarian syndrome (PCOS). Methods The concentration of serum T and DHEA-S in 41 PCOS patients and 50 normal females between 21 and 30 years old were tested by chemiluminescence technique. Results There were significant difference on the serum levels of T and DHEA-S between PCOS patients and normal controls (P<0.05). The diagnosis sensitivity and specificity of PCOS patients by testing serum T level were 82.9% and 86.0%. The diagnosis sensitivity and specificity of PCOS patients by testing serum DHEA-S level were 75.6% and 88.0%. The diagnosis sensitivity and specificity of PCOS patients by combined detection of serum T and DHEA-S level were 92.7% and 96.0%. The diagnosis sensitivity and specificity of combined detection was obviously higher than that of single detection. Conclusion The combined detection of serum T and DHEAS could be used as one of diagnostic criteria of PCOS and worth for widely application.