As quality requirements of packaging continue to increase, flexographic printing still remains very important. Although many substrates are widely used for flexible packaging, bio-based materials are becoming popular because of their sustainable characteristic that results in the usage of bio-based films as a flexo-packaging substrates. This research focused on the printability of flexography using water based acrylic ink on compostable films produced in Thailand such as PLA/PBAT and PBAT/starch. Surface properties of these films were evaluated to observe how they affected the print quality (density, TVI and tone reproduction) of samples under certain conditions (running speed and anilox line screen). The examined properties of substrates were surface roughness, surface morphology and wettability. Results showed that print quality was influenced by substrates' surface properties and printing conditions. In addition, surface treatment was needed, but having limitation. Images of printed surface from SEM and SPM indicated that fracture surface and void of films could lead to defects of print quality. This suggests that raw materials mixed with additives are necessary to improve ink laid-down and hold-out on the surface.