Instructional leadership plays a critical role in enhancing teaching and learning processes, particularly within secondary vocational and special education contexts characterised by diverse learner needs and complex instructional demands. Despite increasing scholarly attention, the intellectual structure and research development in this field remain insufficiently synthesised. This study maps the research landscape on principals’ instructional leadership using a bibliometric approach. Data were retrieved from the Scopus database, yielding 1,108 English-language journal articles within the Social Sciences domain. Bibliometric analyses were conducted using descriptive indicators and network visualisation through VOSviewer to examine publication trends, country contributions, collaboration patterns, and keyword co-occurrence structures. The findings indicate a significant growth in research output, reflecting rising academic interest in instructional leadership across specialised secondary education contexts. However, the research landscape remains geographically concentrated, with limited international collaboration. The thematic analysis reveals an interdisciplinary field integrating pedagogical, technological, and psychosocial perspectives. This study contributes by providing one of the earliest structured mappings of instructional leadership research within the intersecting domains of secondary vocational and special education, offering directions for theory development, cross-national collaboration, and evidence-informed leadership practice.