Despite the abundance of research linking leadership behaviours to organisational effectiveness in various sectors, there is a lack of empirical studies that investigate how leadership behaviours influence performance in the context of research universities. The present study examined the effects of leadership behaviours on departmental performance in public research universities in Ethiopia. The study employed a quantitatively driven embedded type of mixed methods design. The participants of the study were 1176 academic staff (969 instructors and 207 department heads). They were selected from four public research universities using a simple random sampling technique. In addition, 14 key informants were selected using a purposive sampling technique based on their teaching‐learning, research and leadership lived experiences in higher education institutions and interviewed using semi‐structured guiding questions. Quantitative data were collected using questionnaires composed of demographic questions and adapted versions of two scales: Multifactor Leadership Questionnaires and a new tool for measuring global academic performance. The quantitative data were analysed using frequency, percentage, multiple correlations and regression, one sample t‐test, exploratory factor analysis and confirmatory factor analysis. Version 23.0 of Analysis of Moment Structures (AMOS) and SPSS‐23 were used for data analyses. Qualitative data were analysed thematically using open code version 4.03 software. The analyses showed that transactional leadership dimension and teaching‐learning dimension of departmental performance were practised predominantly. Dimensions of leadership behaviour were found to be positively and significantly related to dimensions of departmental performance. The joint contributions of dimensions of leadership behaviour were larger than their separate contributions, thereby supporting the formulated alternative hypotheses. Implications of the findings were discussed.Context and implicationsRationale for the studyLeadership is one of the indispensable factors that determine organisational success. However, empirical study findings that show the effects of leadership behaviours on departmental performance in public higher education institutions were scarce.Why the new findings matterThe new findings matter because the transactional leadership dimension of leadership behaviours and the teaching‐learning dimension of departmental performance are practiced predominantly in the sampled research universities. The findings demonstrated that the stated dimensions of leadership behaviour are positively and significantly related to departmental performance. It is more informative and contributes to knowledge and practice that the combined contributions of leadership behaviours are larger than their separate contributions.Implications for practitionersThe findings of the study have policy and practical implications for improving effectiveness of higher education leadership and departmental performance dimensions: the teaching‐learning process, research and community services in the context of Ethiopian public research universities. This finding further implies that schools and department heads need to use a combination of appropriate leadership behaviours in order to improve departmental performance dimensions.
