This work focused on the valorization of tar derived from rice husk pyrolysis as a precursor of matrices for the encapsulation of active principles. In this regard, the development of novel films based on alginate and eugenol-loaded tar microparticles with suitable mechanical properties and antibacterial activity was studied. Tar microparticles loaded with eugenol were incorporated into sodium alginate films and the effect on the mechanical, thermal and humidity resistance properties were determined, as well as the antimicrobial activity. Films with different crosslinking degrees were also prepared using CaCl 2 , and the eugenol controlled release profiles were evaluated. Crosslinked films exhibited improved mechanical and humidity resistance properties, as well as a lower release rate of eugenol in water. The antimicrobial studies showed that eugenol-loaded films present a higher antimicrobial activity against Staphylococcus aureus. Alginate/eugenol-loaded tar microparticles composites showed an enhancement of antibacterial properties and suitable physical characteristics to be used in active packaging applications.