Violet-throated Metaltail Metallura baroni is a threatened hummingbird species, endemic to the Andes of southern Ecuador. Details about the reproductive biology of this species are largely unknown. In this manuscript, we describe the nest, eggs, and nestlings"™ development based on nine nests found along with the Cuenca-Molleturo-Naranjal road, in Cajas National Park, in 2019. We document a breeding period from March to May, which corresponds to the rainy season. All nests were found in roadside embankments, and were constructed with mosses, small twigs, rootlets, Polylepis sp. (Rosaceae) bark, and Puya sp. (Bromeliaceae) fibers. In all nests, we found two white oval eggs that were exclusively attended by a female across the breeding period. Hatching to fledging period lasted 28-32 days. Nesting at roadsides can be particularly risky due to a high probability of collision with vehicles; thus, an assessment of the breeding success of M. baroni on nests located at roadsides is a research priority for this species. The information provided here increases the knowledge about the natural history of M. baroni.