The Nelicourvi Weaver Ploceus nelicourvi is endemic to Madagascar and information on its breeding biology is scarce and fragmentary. The behavior and parental care of the Nelicourvi Weaver were investigated in Maromizaha Park, eastern Madagascar, from November 2009 to January 2010. We found three nests located 250–700 m apart, suspended 3–10 m above the ground from branches of Nastus spp. (Poaceae) and Trema orientalis (Ulmaceae) above open areas such as streams or trails. The nests were bulky woven structures each with an extended entrance tunnel (ca. 14 cm long). Over a period of about 12 days, the males built the nest structures and the females contributed the nest lining material. The female alone incubated the eggs for about 15 days, and undertook most of the brooding of the young, with only some assistance from the male. During the nestling period, which lasted 13–25 days, both sexes delivered food (mainly beetles, grasshoppers, caterpillars and occasionally small chameleons) to the nestlings. These results suggest that the Nelicourvi Weaver is a socially monogamous bird.