Purpose: The purpose of this paper is to examine how instructional leadership, a concept imported from Western scholarship, has been conceptualized in the Taiwanese context and how principal instructional leadership is realized in schools. The development trajectory of principal instructional leadership is delineated by examining empirical studies in the past two decades. Design/methodology/approach: This paper adopts an exploratory approach to review the Taiwanese empirical literature on principal instructional leadership. A total of 80 studies were systematically analyzed and common themes were identified. Findings: This paper finds that a hybrid model of the conceptualization of instructional leadership has been developed in Taiwan. Principals performed more indirect than direct leadership behaviors. A gap exists between the ideal instructional leader and the reality. Research limitations/implications: The development of a formal theory of instructional leadership is expected as various substantive theories are developed and more data are accumulated. To yield the desired outcome of knowledge acceleration, the coordination of research efforts across scholars and institutions is a must. Practical implications: The articles reviewed suggest less effort spent by principals on the teachers. Yet with a national promotion of teacher learning community, as well as cooperative and collaborative learning in recent years, principal instructional leadership behaviors are expected to rise in terms of ensuring instruction quality and professional development. Originality/value: This paper is an attempt to accumulate knowledge about principal instructional leadership in Taiwan. It is a contribution to the exploration of indigenous perspectives and practices and the understanding and building of educational leadership in Asia.