Which vanara was the son of Vishvakarma?

The vanara who was the son of Vishvakarma was Nala.

In the Ramayana, Nala is a vanara architect associated with the construction of the bridge from India to Lanka. Vishvakarma, the divine craftsman of the gods, is described as his father. Nala’s engineering ability becomes crucial when Rama’s army must cross the ocean to rescue Sita.

Nala is often confused with Nila because the two are closely linked in the bridge episode. Nila is generally described as the son of Agni and as Nala’s twin brother. Some later retellings credit both brothers with building the bridge, while the Valmiki Ramayana gives Nala the leading builder’s role. Nala is therefore the specific answer to the parentage question, not Nila, Hanuman, or Angada.

The bridge is known as Rama Setu and, in some traditions, Nala Setu. Later stories also explain why stones associated with Nala and Nila could float, adding details that vary among regional Ramayana traditions.