The invention discloses a low-GI soft material suitable for 3D printing. Slurry of the low-GI soft material comprises the following raw materials in percentage by weight: 45%-55% of modified proteins, 5%-10% of semen plantaginis shell powder, 5%-10% of low-gluten flour, 10%-20% of chia seeds, 1%-2% of edible salt, 0.5%-2% of skimmed milk powder, 0.02%-0.05% of a coagulator, 3%-10% of a stabilizer, 10%-25% of a sweetening agent and 5%-20% of coconut oil. According to the low-GI soft material suitable for 3D printing, a preparation method of the low-GI soft material, a low-GI biscuit and a preparation method of the low-GI biscuit, 3D printing raw materials prepared through the technology are applied to making of the low-GI biscuit, the functionality and the product added value of the biscuit product can be improved, the requirements of special crowds can be met to the maximum extent, design is flexible, personalized customization can be achieved, besides, batch customized production is achieved, rapid manufacturing becomes economical, and the requirements of modern science and technology development and high-quality life of people are met.