This species is characterized by its shrub habit, dense hirsute pubescence, somewhat large (for Gonzalagunia) ovate leaves with stout developed petioles, pseudoaxillary or truly axillary spiciform inflorescences with the flowers subsessile in subsesile congested groups of 5-7, regularly developed narrowly triangular bracts ca. 5 mm long, deeply lobed calyx limbs with acute lobes ca. 1 mm long, and 4-locular white fruits. The inflorescences have peduncles 0.5-1.5 cm long and flower-bearing portions 2-5 cm long. One flower bud has been seen, with the tube ca. 2 mm long and lobes ca. 1.5 mm long.

Gonzalagunia congesta is not very similar to other species of this genus. It is somewhat similar to Psychotria pilosa, with bilobed stipules and fruits with two pyrenes.