Viewed from the perspective of attachment theory, coping with the separation and divorce of parents requires that children reorganize their mental model of attachment. Secure attachment models may be disrupted, while insecure attachment models may be strengthened. According to findings from research on divorce, this process of family reorganization takes about two years. Attachment representations in middle childhood can be assessed by new methods that rely on the symbolic medium of story completion in doll play. Based on five coded attachment story narratives, the "Attachment Story Completion Task" (ASCT) by Bretherton and Ridgeway, and the "German Coding and Classification System" by Gloger-Tippelt and Konig, permits the assessment of secure, avoidant, ambivalent and disorganized attachment representations reliably, and to rate attachment security on a four-point-scale. In this study we compare the attachment representations in ASCT of 51 children from two parent families with 60 six-year-old children from one parent, all mother families who experienced separation/divorce, and were still in the phase of family reconstruction. The children of single mothers demonstrated fewer secure and more insecure attachment representations, in particular more avoidant ones. Moreover, in the children from one parent, but not from two parent families a significant gender effect emerged. Results have been discussed considering further risk factors in the one parent families and possible influences of children's attachment representations in the school setting. (Contains 3 tables.)