Previous scholarship has established a connection between information literacy and writing, highlighting in particular how writing theories could inform our understanding of information literacy. This paper continues this line of inquiry and discusses how information literacy and writing can mutually inform and support each other. Based on a review of major theoretical developments in both fields, this paper proposes a three-dimensional model of information-based academic writing (IBAW) in higher education that foregrounds information literacy as an integral part of the writing process. Specifically, the model illustrates how writing tasks situated in specific rhetorical, disciplinary, and information contexts activate one's knowledge base and generate information needs, which then guides the iterative information literacy and writing processes, as regulated by one's affective and metacognitive strategies, to generate new knowledge. The IBAW model, with the three dimensions and specific factors explicitly identified, also reflects truthfully the defining features of information literacy as contextual, process-oriented, value-laden, interactive, strategic, and always goal-oriented. As such, it also serves as a contextualized, process-oriented, and task-based model for information literacy instruction and development. Implications for how information literacy and information-based academic writing could be taught based on this proposed model are then discussed.