Purpose: This investigation examined the comprehension of third person singular /s/ in 30 African American English (AAE)-speaking children as a subject-number agreement marker on a comprehension task. Method: A comprehension task was presented to 30 typically developing AAE-speaking children between the ages of 4 and 6. The children were randomly assigned to 1 of 2 groups to hear prerecorded counterbalanced stimuli. The comprehension task was designed to mask plurality of subject; therefore, the children had to focus on the verb as an indicator of subject number. Results: Repeated measure analysis revealed that AAE-speaking children in this investigation did not understand third person singular /s/ as a number agreement marker. An additional analysis, d' (pronounced "d prime"), indicated that the AAE-speaking children are not sensitive to the third person singular /s/ as a clue to subject number. Clinical Implications: The inclusion of comprehension tasks of third person singular /s/ to help diagnose language impairment in this population may be problematic.