Pandrosus ("the all-dewy one") is a figure in Greek mythology and a daughter of Cecrops.

According to Apollodorus, Hephaestus attempted to rape Athena but was unsuccessful. His semen fell on the ground, impregnating Gaia. Gaia didn't want the infant Erichthonius, so she gave the baby to Athena. Athena gave three sisters: Herse, Pandrosus and Aglaulus the baby in a small box and warned them to never open it. Aglaulus and Herse opened the box which contained the infant and future-king, Erichthonius. The sight caused Herse and Aglaulus to go insane and they threw themselves off the Acropolis.

An alternative version of the same story is that, while Athena was away from Athens, bringing a mountain from Pallena to use in the Acropolis, the sisters, minus Pandrosus again, opened the box. A crow witnessed the opening and flew away to tell Athena, who fell into a rage and dropped the mountain (now Mt. Lykabettos). Once again, Herse and Aglaulus went insane and threw themselves to their deaths off a cliff.

Pandrosus and Hermes later had a son, Ceryx.

Alternative: Pandrosos