Hibiscus kokio subsp. saintjohnianusis is a shrub to small tree that grows 1 to 7 meters tall, with distal stems covered in stiff, sessile, bifurcate to stellate hairs. The leaves are simple and alternate, with elliptic to oblong-elliptic, ovate, or sometimes obovate blades, measuring 3 to 21 cm long and 1.5 to 11 cm wide. These leaves have an acute to acuminate apex and a broadly cuneate to obtuse base. They are green, glossy, and subcoriaceous with crenate to serrate margins that can be undulated or occasionally entire. The flowers are solitary, located near the branch ends, with articulate pedicels of 1 to 4 cm. The involucral bracts are subulate to lanceolate-linear, 7 to 17 mm long. The calyx is yellowish, tubular, and the corolla ranges from actinomorphic (radially symmetric) to moderately zygomorphic (bilaterally symmetric), typically orange to orangish red, sometimes yellow, and is 4.5 to 7 cm long. The stamens form an exserted monadelphous (all the filaments of the stamens are united into a single bundle to form a tube-like structure) column, with the ovary being superior and 5-celled, leading to a style that exceeds the staminal column. The fruit are loculicidally-dehiscent capsules, pale brown, obovoid, 1.6–1.8 cm long; obscurely pubescent; exocarp and endocarp sometimes separating at maturity. The seeds are dark brown, angular-reniform, 4-5 mm long, sparsely pubescent, with or without endosperm. It occurs in scattered populations from dry to wet forests between 150-1,100 meters.