Emerging evidence suggests that as with adults, dismissing children underreport their psychological distress relative to physiological indicators of their experience (startle response, neural signals). In this report, we extend these observations to neuroendocrine reactivity. One hundred and six 8-12-year-old children completed the Child Attachment Interview and a computer-based paradigm comprised of vignettes reflecting vulnerability in interpersonal contexts. Dismissing children's cortisol responses remained comparable from pre-to-post paradigm, while secure children's cortisol responses decreased from pre-to-post paradigm. Furthermore, compared to secure children, dismissing children reported less distress than their cortisol response would suggest. Implications for dismissing children's coping and self-regulation are discussed. © 2013 Wiley Periodicals, Inc.