Wikimedia Commons has media related to Flora of Northwestern United States.
- This category includes the native flora of the Northwestern United States, within the United States, in North America.
- Taxa of the lowest rank are always included. Higher taxa are included only if endemic.
- For the purposes of this category, the "Northwestern United States" is defined in accordance with the World Geographical Scheme for Recording Plant Distributions. That is, the geographic region is defined by the political boundaries of its constituents: