As many as 20% of children are need in of mental health services but only a small percentage receive them. Primary care pediatricians are often the first providers to see these children so it is critical to understand how they manage their care. Therefore, we developed a vignette-based survey to obtain data about pediatricians’ mental health-related diagnostic accuracy, confidence and comfort level in diagnosis and management, and decisions related to care. Pediatricians (N = 106) responded to one of two vignettes, one describing a child with symptoms consistent with ADHD, inattentive type, and the other with symptoms of a depressive disorder. Overall diagnostic accuracy was ~60%, although pediatricians who received the ADHD vignette indicated greater confidence in their diagnosis and greater likelihood of providing treatment themselves. Those who received the ADHD vignette were also more likely to conduct a next level assessment and not to refer to a specialist. Participant characteristics, other than level of interest in mental health, were generally not associated with accuracy, confidence, comfort level, and decisions. Neither years in practice nor completion of a residency rotation in developmental and behavioral pediatrics yielded significant differences in or correlations with diagnosis and management. Consistent with previous reports, pediatric primary care providers vary in their responses to mental health concerns, depending upon the symptom presentation. Primary care providers in our study also appear to value consultation with mental health specialists, supporting the importance of interprofessional collaboration in caring for children with mental health related concerns.