The invention discloses an internal dyeing method of a dental zirconium oxide restoration body, belonging to the technical field of ceramic preparation. The internal dyeing method comprises the following steps: pre-treating a pre-sintered dental zirconium oxide restoration body; soaking in dyeing liquid; taking out and sufficiently drying; and carrying out final sintering in stages. The internal dyeing method disclosed by the invention solves problems that an existing dental zirconium oxide restoration body internal dyeing process is non-standard in operation, uneven in dyeing and not beautiful, and is standard and simple in operation, and good in dyeing effect.