Background: As part of our search for new potential natural resources to eradicate infection, we have revealed the prominent potency of massoia bark (Massoia aromatica Becc, Lauraceae) in combating immunosuppressed-related infection. Materials and Methods: The extract was prepared by macerating the pulverized dried bark in ethanol 95%, followed by solvent evaporation. The oil was extracted from the dried bark by steam-hydrodistillation of which preparative thin-layer chromatography was performed on the oil to isolate the active constituent, C-10 massoia lactone (ML). Anti-biofilm assay against Candida albicans was conducted on polystyrene 96 wells microtiter plates, followed by a confocal laser scanning microscope observation to get three-dimensional profiles of the affected biofilms. Effects on the hyphae development inoculated on RPMI-1640 agar plates were observed for 7 days. Influences of samples on mice macrophage phagocytosis were examined by an in vitro technique. Samples concentration tested were in the range of 2.0–0.0625 mg/mL and done in triplicate. Results: Massoia bark extracts (oil and solid phase) and ML exhibited promising activities as anti-biofilm against C. albicans at IC50 0.074% v/v, 271 μg/mL and 0.026 μg/mL, respectively. The ML did not inhibit the hyphae development at the concentration tested; however, the extracts showed inhibition at 62.5 μg/mL. Macrophage phagocytosis stimulation was correlated to the ML content. Conclusion: Massoia bark is potential to be developed as anti-infective in immunosuppressed condition of which the C10 ML (C10H16O2) plays a major role in exerting activity.