used in many applications such as cosmetics, agriculture, and the food industry owing to their biodegradability and low toxicity compared to chemical surfactants 8−10) . In addition to these benefits, biosurfactants have properties that are suitable for cosmetic applications, such as compatibility with human skin and skin surface moisturizing 10) .Furthermore, consumers pay more attention to natural products when considering environmental sustainability 11) . Therefore, biosurfactants have scope to be further deployed in the cosmetic industry. For instance, in addition to their potential skin benefits, the eco-friendly characteristics of biosurfactants have attracted attention for cleaning applications and their potential applications in haircare 12) .Sophorolipids are biosurfactants that possess both capacities for the disruption 13−16) and removal 17) of biofilms. Owing to the high complexity of biofilms, it is challenging to understand which of their components should be target-Abstract: Biofilms are communities of microorganisms that have been widely studied because they can cause hospital-acquired infections and skin disorders. Polysaccharides secreted by microorganisms are constituents of biofilms, contributing to their adhesion and mechanical stability. Sophorolipids are biosurfactants with the ability to disrupt and remove biofilms. Biosurfactants have been targeted as potential substitutes for classical petrochemical-based surfactants in cosmetics. In this study, we fabricate a β-glucan film as a model biofilm, and quartz crystal microbalance with dissipation monitoring (QCM-D) measurements are used to assess the biofilm removal. The viscoelasticity of the β-glucan films is monitored while sophorolipid solutions are introduced into the system, and we found that the film removal performance increases with the sophorolipid concentration. In addition, Δf (change in frequency)-ΔD (change in energy dissipation) plot analyses reveal that two processes are involved in the removal mechanism. The first process involves the adsorption of water (hydration) on the β-glucan film. The second process involves the removal of the β-glucan film from the sensor surface. Furthermore, it is suggested that sophorolipids interfere with the hydration of the β-glucan film and suppress increases in its viscosity. This is expected to be an essential factor for the removal of the β-glucan film. Sophorolipids, therefore, show potential for use in cosmetics as an eco-friendly agent for biofilm removal.