Abstract
The study examined the relationship between family structure and disciplinary behaviour among senior secondary school students in the Federal Capital Territory (FCT), Abuja. A descriptive correlational survey design was adopted, and 381 students were selected through stratified and simple random sampling techniques. Data were collected using two researcher-developed instruments, namely Family Structure Questionnaire (FSQ) and Disciplinary Behaviour Questionnaire (DBQ). Data were analysed using Pearson Product Moment Correlation at 0.05 level of significance. The findings revealed that nuclear and extended family structures had significant positive relationships with disciplinary behaviour, reconstructed family structure had a significant negative relationship, while single-parent family structure showed a weak but significant positive relationship. The study concluded that family structure significantly influenced students' disciplinary behaviour and recommended strengthened parenting practices, effective guidance and counselling services, and enhanced home-school collaboration to promote positive behavioural outcomes.