The aim of this study was to explore school nurses’ experience of challenges related to documenting schoolchildren’s psychosocial health in Sweden. Six focus group discussions were carried out. Areas for discussions included questions about situations, especially challenging to document as well as what constrains and/or facilitates documenting psychosocial health problem issues. Qualitative content analysis was used for interpreting the data. The analysis resulted in one overarching theme: having to do one’s duty and being afraid of doing wrong; and three subthemes: uncertainty related to one’s own ability, concerns related to future consequences, and strategies to handle the documentation. School nurses relying on their intuition and using a structured documentation model may increase the opportunities for a reliable documentation. To further develop their professional skills with regular, clinical supervision can be of great importance. This in turn may increase contributions to research and development for the benefit of schoolchildren’s psychosocial health.