Abstract: School-based professional development (SB-PD) is intended to bring teacher learning closer to classroom realities, yet its usefulness for inclusive education depends on the relevance of its content and the way learning activities are delivered. This study examined the content and delivery methods of SB-PD initiatives implemented in public primary schools in Kongwa District, Tanzania, with particular attention to their capacity to support teachers who work with autistic learners. The study adopted a concurrent mixed-methods orientation. For the objective reported in this paper, quantitative evidence came from 52 teacher questionnaires across three public primary schools, while school professional-development records were reviewed to corroborate reported practices. Quantitative data were summarized using frequencies and percentages, and documentary evidence was analysed thematically. Results showed that 59.6% of teachers reported SB-PD occurring once a month and 23.1% less frequently. Content concentrated on subject-matter refreshers (76.9%), lesson planning (65.4%) and classroom assessment (51.9%), whereas behaviour management (25.0%) and technology integration (13.5%) received limited attention. Whole-staff workshops or lectures dominated delivery (92.3%), while peer observation (23.1%), demonstration lessons (21.2%) and teacher learning circles (5.8%) were uncommon. School records contained no documented autism-specific training hours or materials. The study concludes that SB-PD is present but insufficiently specialized and practice-based for inclusive autism support. It recommends institutionalizing autism-focused modules, peer coaching, demonstration lessons and sustained follow-up within school-based professional learning.