Candida biofilms are self-organized microbial communities growing on the surfaces of host tissues and medical devices. These biofilms have been displaying increasing resistance against conventional antifungal agents. The roots of Scutellaria baicalensis have been widely used for medicinal purpose throughout East Asia. The aim of the present study was to evaluate the effect of S. baicalensis aqueous extract upon the preformed biofilms of 10 clinical C. albicans isolates, and assess the mechanism of the antibiofilm activity. Its effect on preformed biofilm was judged using an XTT reduction assay and the metabolic activity of all tested strains were reduced ($57.7{pm}17.3$%) at MIC values. The S. baicalenis extract inhibited (1, 3)-${eta}$-D-glucan synthase activity. The effect of S. baicalensis on the morphology of C. albicans was related to the changes in growth caused by inhibiting glucan synthesis; most cells were round and swollen, and cell walls were densely stained or ruptured. The anticandidal activity was fungicidal, and the extract also arrested C. albicans cells at $G_0/G_1$. The data suggest that S. baicalensis has multiple fatal effects on target fungi, which ultimately result in cell wall disruption and killing by inhibiting (1, 3)-${eta}$-D-glucan synthesis. Therefore, S. baicalensis holds great promise for use in treating and eliminating biofilm-associated Candida infections.