'Juniperus standleyi is an evergreen coniferous shrub or small to medium-sized tree growing to 5–15 m (rarely 20 m) tall. The leaves are of two forms, juvenile needle-like leaves 5–7 mm long on seedlings and occasionally (regrowth after browsing damage) on adult plants, and adult scale-leaves 1–1.5 mm long on older plants; they are arranged in decussate opposite pairs or whorls of three.
The cones are globose, berry-like, 6–9 mm diameter, blue-black with a thin pale waxy coating, and contain three to six seeds; they are mature in about 18 months. The male cones are 1.5–2 mm long, and shed their pollen in spring. It is dioecious with male and female cones on separate plants.