Multifunctional poly(tartar amides) have been synthesized and used as bio-inspired antifreeze additives. It is shown that these polymers strongly interfere with the crystallization process of water in comparison to commercially available commodity polymers. While the addition of the poly(tartar amides) results in minor freezing point depression, as is shown by differential scanning calorimetry, a strong change in the ice crystal morphology is evident. Wide-angle X-ray scattering and optical microscopy indicate that the hexagonal structure of undisturbed ice-crystals is oriented and partly deformed.