Given that teacher shortage is an international problem, teacher job satisfaction merits closer attention. Not only is job satisfaction closely related to teacher retention, but it also contributes to the well-being of teachers and their students, overall school cohesion and enhanced status of the teaching profession. This study investigates the relations between teacher job satisfaction, school working conditions and teacher characteristics for eighth grade mathematics teachers. The study employs TIMSS 2015 (Trends in International Mathematics and Science Study) data from Sweden. Confirmatory factor analysis and structural equation modelling are used as main methods. Results demonstrate a substantial association between school working conditions and teacher job satisfaction. More specifically, teacher workload, teacher cooperation and teacher perceptions of student discipline in school were the factors most closely related to teacher job satisfaction. As to teacher characteristics, female teachers, teachers with more exposure to professional development and more efficacious teachers tended to have higher levels of job satisfaction. In addition, it was found that the relationship between the extent of teacher cooperation and job satisfaction was more pronounced for male teachers, while student discipline was more important for job satisfaction of teachers with lower self-efficacy beliefs. Implications for policy are further discussed.