The invention belongs to the technology for gene engineering, and discloses a method for increasing tanshinone content of salvia miltiorrhiza hairy roots by transferring SmGGPPS gene. In the prior art, the growth cycle of the salvia miltiorrhiza is long; the tanshinone content is low, and the requirement of the human medical treatment for the tanshinone content cannot be met. The method comprisesthe following steps of: cloning a coding sequence of the SmGGPPS gene from salvia miltiorrhiza, and constructing a plant high-efficient expression vector; genetically transforming salvia miltiorrhizaleaves to obtain the salvia miltiorrhiza hairy roots with transferred SmGGPPS gene; analyzing the expression condition of the SmGGPPS gene in the transgenic salvia miltiorrhiza hairy roots by a semi-quantitative RT-PCR method; measuring the total tanshinone content including cryptotanshinone, tanshinone I and tanshinone II A of the transgenic salvia miltiorrhiza hairy roots by high performance liquid chromatography; and measuring the antioxidant activity of cryptotanshinone of the transgenic salvia miltiorrhiza hairy roots by a diphenyl picryl-hydrazyl (DPPH) method. The method has the advantages of obviously increased total tanshinone content of the salvia miltiorrhiza hairy roots, reliable effect, low cost of tanshinone, and no environmental pollution during manufacturing.