Many studies tried to innovate wood bioadhesives using renewable resources. This research attempted to synthesize wood bioadhesive using cassava starch and polyvinyl alcohol (PVA). As a new cross-linking agent, citric acid was added to the bioadhesive to ensure the bonding between cassava starch and PVA. PVA and citric acid contain hydroxyl groups that can initiate polymerization with starch. The synthesis of bioadhesive has three steps, namely, acid hydrolysis, oxidation, and cross-linking reactions. The operating condition was set at 70°C under atmospheric pressure for 90 minutes. The amount of added PVA varied at 0%, 10%, 20%, 30%, and 40% relative to the weight of cassava starch. Physical properties such as viscosity, solid content, shelf life, and dry and wet shear strength were analyzed to determine the best composition of starch and PVA. Results showed that the addition of PVA could enhance the bioadhesive's properties, especially its dry and wet shear strength.