Reflection is a vital component of improving one’s teaching practice, particularly for preservice teachers. Current research on preservice teacher reflection often examines the gaps, or deficits, of preservice teachers’ reflective practices. The aim of this paper is to propose a conceptual framework and methodological approach for exploring preservice teachers’ reflections on teaching mathematics from an asset-based perspective. Building upon prior literature, we created a conceptual framework called Preservice Teacher Noticing of Classroom Practices, which provided a lens for seeing preservice teachers’ assets as it relates to reflection. Guided by this conceptual framework, we analyzed 18 preservice teachers’ written reflections of their own teaching practice to explore their assets of reflection. The findings revealed that preservice teachers used existing intellectual resources (i.e., assets) to solve problems of practice, and an illustrative example from the data demonstrated how preservice teachers can productively build upon their current assets toward improved reflective practices. Implications for research include new theoretical and methodological approaches for analyzing preservice teachers’ reflections. Implications for practice include new strategies for supporting preservice teachers in building upon their assets toward improved reflective practices.