In the course of searching for potent chitin synthase 1 inhibitors from natural resources, Streptomyces sp. A6705 was found to exhibit potent inhibitory activity against the chitin synthase 1 from C. albicans (CaCHS1p). As a result, the inhibitor was isolated and identified using a series of chromatographies. Through chemical analyses with UV spectrophotometry, MS spectrometry, and various NMR techniques, the inhibitor was identified as N,N-bis(2-phenylethyl)urea. The compound exhibited strong inhibitory activity against the chitin synthase 1 from C. albicans with an $IC_{50}$ of 14 ${mu}g$/ml, representing a similar inhibitory activity to that of the well-known chitin synthase inhibitor, polyoxin D ($IC_{50}$ 15 ${mu}g$/ml). However, the compound showed no inhibitory activity against the chitin synthase 2 of Saccharomyces cerevisiae up to 280 ${mu}g$/ml, which is structurally and functionally analogous to CaCHS 1 p. In addition, the compound exhibited weak antifungal activities against Cryptococcus neoformans and Rhizoctonis solani.