Preschools in Sweden are among the most stressful places to work in – for adults. But young children also spend full days in this environment, being affected by the stress. The question is to what extent? Limited research has been done about children’s perception of stress inSwedish preschools, which is why this study is relevant. The purpose of the study is to develop knowledge about children's stress in preschool from their perspective. Addressing which stressors are common among children in preschools, how children experience stress when they are there, and finally what the teachers can do to alleviate children's stress in preschools. The results have been collected using semi-structured qualitative interviews, where eleven children and five preschool teachers have been interviewed in three different preschools. Their responses have been analyzed using qualitative content analysis, and the results show that children experience stress in preschool when there are loud noises, conflicts, when someone destroys something they have created, when sudden, unforeseen events occur or when they are faced with new, unknown situations or people. The stress makes them feel sad, angry and anxious and gives them headaches, stomachaches, tremors and shivers. According to the study, simple measures can be introduced to reduce stress in the daily preschool activities, for example by dividing the children into smaller groups, practicing mindfulness/yoga, spending time in the forest, playing in the sandbox and engaging in value-based work.