Contrarily to state-of-the-art formula ons, the novel approach presented herein relies on a biobased and addi ve-free ink. Notably, the use of chlorophylls inherent in the microalgae extracts circumvents the issue of using non-biobased and toxic photoini ators or absorbers. The printability window, curing, resolu on and minimal features have been thoroughly studied. It was possible to fabricate intricate and complex 3D geometries with different degrees of overhanging structures and sub-micron resolu on. Furthermore, the biocompa bility of the printed microalgae-based structures was verified through cell viability studies. This work highlights the vast poten al of microalgae as a highly unexplored yet promising feedstock for light-based 3D prin ng. The usage of microalgae from two different taxonomic families also demonstrates the universality of the presented approach. We believe that the use of microalgae will bring forth a new fron er in 3D prin ng toward sustainable biobased and func onal materials, with poten al applica ons including biocompa ble implants or non-toxic cell scaffolds.