The main aim of this work is to see if the quality of the mother-child relationship, specifically the dimensions of affection and conflict, interferes with the student's writing performance. The study involved 88 children of both sexes, aged between 9 and 11, enrolled in primary school in public and private schools located in the Greater São Paulo region. The instruments used for data collection were: Raven's Coloured Matrices Test, Writing Learning Difficulties Assessment Test and the Familiogram test. The data was analysed using descriptive and inferential statistics. The results suggest that there was no statistically significant correlation between the child's writing performance and the quality of the mother-child relationship. The results found deserve to be considered with caution, emphasising that the mother-child relationship cannot be understood as the main cause that best explains the failure in the child's writing development.