OBJECTIVES: The objective of this study was to determine predictors of sexually transmitted infection (STI) testing among adolescent females presenting to an urban pediatric emergency department (ED) with symptoms potentially suggestive of an STI. METHODS: This was a secondary analysis of data collected in a prospective prevalence study of STIs among a consecutive sample of symptomatic females aged 14 to 19 years presenting to a pediatric ED with lower abdominal or genitourinary complaints. The outcome of interest was performance of an STI test. Correlates of interest included patient age, race, insurance status, chief complaint, presence of comorbid conditions, and treating physician sex. RESULTS: Of the 328 adolescent females who presented to the ED with STI-related complaints and met inclusion criteria, 15.6% did not undergo STI testing. Univariable analysis revealed that black or African American race (odds ratio [OR] = 4.98, 95% confidence interval [CI] = 2.67 to 9.30) and nonprivate insurance (OR = 3.47; 95% CI = 1.83 to 6.58) were significantly associated with the performance of STI testing. In a multivariable model, only black or African American race (OR = 3.94; 95% CI = 1.96 to 7.91) remained significantly associated with the performance of STI testing. CONCLUSIONS: A substantial number of adolescent females who presented with complaints suggestive of an STI did not undergo STI testing, and a racial disparity in STI testing was noted. The racial disparity in rates of STI testing among symptomatic adolescent girls presenting to the ED warrants further study to confirm validity, to determine if disparity reflects physicians' biases, and to inform strategies for controlling the present epidemic of STIs in adolescents.