The key aspect of Asperger’s syndrome is durability in time. Deficits, especially social ones, which are typical of the disorder, remain unchanged throughout life. However, adaptation is sometimes improved, and some people with Asperger’s syndrome may achieve a relative degree of social integration. The aim of the study was to investigate the relationship between the severity of the disorder in children with Asperger’s syndrome and their mothers’ stress coping styles – measured at two points in time (the second measurement six years after the first one). The relationship between the severity of the disorder in children and their mothers’ stress coping styles was also analysed with respect to the mother’s age and the mother’s professional work. The overall severity of the disorder in children with Asperger’s syndrome decreases from the time of the initial study. Over time, mothers of children with Asperger’s syndrome are more likely to use the avoidance coping style (at the level of statistical trend). Limitations of verbal communication (in the first measurement) and deficits in the child using visual contact to adjust the social interactions (in the second measurement) may reduce their mothers’ readiness to apply the task-oriented coping style, especially in the context of chronic stress associated with disorders in children. In the course of the disorder in children, a number of statistically significant correlations between the severity of these disorders, mothers’ coping styles and the sociodemographic variables of mothers were also found.