In recent years, information and communication technologies (ICTs) have emerged as a pivotal strategic element in public administration, with the objective of addressing societal challenges and creating public value. To achieve success, public entities must make strategic IT decisions that ensure that IT initiatives align with and extend the society's strategy and goals. In this context, Strategic Information Systems (SIS) plays a pivotal role. Nonetheless, the effort in SIS on public administration is not only controversial but also different among public entities. The existing research in this area is scarce and fragmented, requiring not only a critical outlook from an interdisciplinary field of knowledge, but also to explore its intellectual core. Using the systematic literature review (SLR) method, this paper analyzes prior research in SIS on public entities, focusing on each stage of the strategic planning process (determinants, strategic management process and outcomes). Findings reveal the need of holistically examining the SIS process, providing public managers appropriate tools for improving strategic implementation success rate.