Abstract: The ethical issue of human life circumstances in Marx's thought of ecological community clarifies the inherent nature of human existence, the ideal state of human life circumstances, the necessary mode of human-nature relationship that supports such ideal circumstances, the actual state of human-nature relationships and their fundamental impact on human life circumstances in different types of communities, and the ideal community that achieves reconciliation between humanity and nature and the consequent universal optimization of human life circumstances. Marx's ecological community thought analyzes the actual state of human-nature relationships and their fundamental impact on human life circumstances in different types of communities, exposes the alienation of human-nature relationships in capitalist communities and the resulting human life predicaments, and envisions the reconciliation between humanity and nature in a genuine community and the universal optimization of human life circumstances based on it. Respecting the inherent nature of human existence, resolving the alienation of human-nature relationships and the resulting human life predicaments, and promoting the reconciliation between humanity and nature along with the universal optimization of human life circumstances constitute the highest "good" pursued by Marx's ecological community thought.Inspired by the ethical issue of human life circumstances in Marx's ecological community thought, humanity should take the reconciliation between humanity and nature and the optimization of circumstances based on it as the fundamental value orientation. From the perspective of systemic justice in "human-nature relationships" and "human life circumstances," transcending institutional differences and interest barriers, we should jointly build a community of life for humanity and nature and a shared ecological future for humanity. Together, we will promote the modernization and globalization of harmonious coexistence between humanity and nature, and construct a new form of civilization characterized by the harmonious of humanity and nature.