The current study examined teacher competence and contextual factors associated with teacher-reported stress in low-income urban elementary schools. Using a sample of 106K-5th grade teachers from 14 low-income urban elementary schools, associations between observed use of instructional and behavior management practices, teacher-reported stress, perceived instrumental and emotional supports, class-wide student academic performance, and behavioral functioning were examined. Teacher-reported stress was significantly related to perceived emotional support, instrumental support, class-wide student academic performance, and class-wide student behavioral functioning. Instrumental and emotional supports, observed instructional and behavioral management practices, and class-wide student academic and behavioral functioning jointly predicted teacher stress. Results from a dominance analysis identified class-wide behavioral functioning, and emotional and instrumental support as the strongest predictors of teacher stress. Study limitations and implications for research and practice are discussed.