This study examined the relationship between workplace support and teacher job satisfaction in primary schools in the context of the national school-based Teachers’ Continuous Professional Development (TCPD) in Tanzania. The study was guided by Herzberg’s Two-Factor Theory and conceptualised workplace support as the combination of leadership support, collegial collaboration, adequate time and resources, and teamwork around TCPD activities. A quantitative cross-sectional design was used to analyse a survey dataset of 1,302 respondents drawn from eight regions of Tanzania-Dodoma, Tanga, Pwani, Mara, Rukwa, Singida, Katavi and Simiyu regions. The analysis focused on a workplace-support scale based on four items and an overall teacher job satisfaction scale based on nineteen items. Descriptive statistics, reliability analysis, Pearson correlation, and hierarchical regression were used to address the study objectives and test the hypothesis. The workplace-support scale showed acceptable internal consistency (α = .731), while the job-satisfaction scale showed excellent internal consistency (α = .965). Teachers revealed high workplace support (M = 4.09, SD = 0.53) and high job satisfaction (M = 4.16, SD = 0.49) on a five-point Likert scale. Workplace support was strongly and positively associated with overall job satisfaction (r = .700, p < .001), and the relationship remained significant after adjustment for gender, education level, and teaching experience (β = .654, p < .001). The lowest-rated workplace-support item concerned time and resources for participation, indicating that implementation conditions remain uneven even where collegial and leadership support systems are strong. The findings suggests that supportive school environments are significance not only for teacher learning within TCPD but also for teachers’ morale, sense of belonging, and professional growth. The paper concludes that school-based professional development reforms are more likely to be sustained when they are designed not simply as technical training arrangements but supportive work environments for supporting day-to-day teachers’ teaching experience of the profession. Therefore, the study recommends that educational leaders should institutionalise TCPD to be integral part of teachers’ daily professional practice by creating time for participation, enhancing Communities of Learning (CoL), and ensuring equitable access to resources needed for meaningful engagement.