The Canadian public health sector's foundational values of social justice and equity, and its mandate to promote population health, make it ideally situated to take a strong lead in addressing persistent and unacceptable inequities in health between socially disadvantaged, marginalized or excluded groups and the general population. There is currently much attention paid to improving understanding of pathways to health equity and development of effective population health interventions to reduce health inequities. Strengthening the capacity of the public health sector to develop, implement and sustain equity-focused population health initiatives - including readiness to engage in a social justice-based equity framework for public health - is an equally essential area that has received less attention. Unfortunately, there is evidence that current capacity of the Canadian public health sector to address inequities is highly variable. The first step in developing a sustained approach to improving capacity for health equity action is the identification of what this type of capacity entails. This paper outlines a Conceptual Framework of Organizational Capacity for Public Health Equity Action (OC-PHEA), grounded in the experience of Canadian public health equity champions, that can guide research, dialogue, reflection and action on public health capacity development to achieve health equity goals.