Paxistima myrsinites is a small, spreading shrub with slender, woody branches that are approximately square in cross-section, and ridged. Leaves are dark green, relatively thick, arranged in opposite pairs, and attached by very short stalks. Leaf margins are lined by small, sharp, well-separated teeth. Leaf tips may be rounded or somewhat pointed. New growth leaves are distinctly lighter in color.
Between one and three flowers form in spring and summer at the leaf axils; they consist of four unfused, triangular green sepals and four oval red petals, all similar in size (less than 0.05 inches long). At the center are four filaments topped by yellow anthers, and a greenish stigma.