The invention discloses a dye formula for an indigo blue printing fabric, and relates to the technical field of dyes. Dye comprises the following components of polygonum tinctorium lour, baphicacanthus cusia bremek, acrylic resin, an enzyme preparation, a color fixing agent, a dispersant, an antibacterial agent, an antistatic agent and water, wherein the dye comprises the components of, in parts by weight, 30-50 parts of the polygonum tinctorium lour, 20-30 parts of the baphicacanthus cusia bremek, 3-7 parts of the acrylic resin, 4-6 parts of the enzyme preparation, 2-6 parts of the antibacterial agent, 3-5 parts of the antistatic agent, 1-3 parts of the color fixing agent, 1-3 parts of the dispersing agent and 60-80 parts of the water. According to the formula, plant raw materials serve as main raw materials, safety and non-toxicity are achieved, natural and environment-protecting effects are achieved, and the cost is low; and by adding the acrylic resin, the color fixing agent, the dispersing agent, the antibacterial agent and the antistatic agent, the printed indigo blue printing fabric is uniform in coloring, pure in color, not prone to fade, has the antibacterial and antistatic effects, and is wide in application range.