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An effective method for preparing food-grade three-dimensional (3D) printing materials was the use of highly concentrated oil-in-water emulsions. This research reported 3D printable materials constructed from food-grade high internal phase Pickering emulsions (HIPPEs) that were stabilized by ε-poly- l -lysine grafted cellulose nanofiber (ε-PL-TOCNs). The ε-PL-TOCNs were prepared via ε-poly- l -lysine grafting of 2, 2, 6, 6-tetramethylpiperidine-N-oxyl (TEMPO)-oxidized cellulose (TOC) and the successive mechanical treatment. Subsequently, the chemical structure, microstructure and surface properties of ε-PL-TOCNs were characterized. The results showed that the prepared ε-PL-TOCNs had excellent dispersion performances, cationic properties brought by amino groups, and hydrophilic/hydrophobic functions of chain structure, which confirmed the feasibility of preparing HIPPEs. The HIPPEs with an internal phase volume fraction of 82 % were obtained at 0.8 wt% ε-PL-TOCNs concentration and pre-emulsification followed by continuous oil feeding. The HIPPEs' storage stability, morphology, and rheological behavior were further discussed. The ultra stable HIPPEs with apparent shear-thinning behavior and high solid viscoelasticity were successful produced, which was suitable for 3D printing. This work expanded the application of nanocellulose in emulsions field and provided a new thinking to prepare food-grade 3D printable materials and porous foam. • ε-poly- l -lysine grafted cellulose nanofiber (ε-PL-TOCNs) has improved emulsifying performance. • HIPPEs are produced using ε-PL-TOCNs and without adding extra solid particles. • The volume fraction of HIPPE stabilized by 0.8 wt% ε-PL-TOCNs is up to 82 %. • HIPPEs exhibit food-grade 3D printability due to viscoelastic solid-like behavior. • HIPPEs can easily further prepare porous foam. [ABSTRACT FROM AUTHOR]