The effects of applying exogenous Mn on growth, enzyme (PPO and POD) activities and tanshinones accumulation of cultivated Salviae Miltiorrhizae Bunge were studied under condition of sand culture. The results showed that exogenous Mn promoted the growth of shoot and root under suitable applied amount of Mn. The biomass dry weight of the shoot and root in the treatment under 14 mg/kg of Mn concentration were both the highest, which were 38.08% and 19.77% higher than that of Mn0 treatment respectively. Little higher Mn concentration could inhibit root growth. Mn concentrations in steam, leaf and root increased with the increase of Mn applied, and Mn concentrations in steams and leaves were higher than that in roots. Chlorophyll contents in leaf increased under higher Mn concentrations (21 mg/kg and 28 mg/kg). Proper Mn application could increased the activities of PPO and POD, which increased with the increase of Mn concentration as Mn applied doses did not exceed 21 mg/kg. Mn application could also promote the accumulation of three tanshinones in roots. Activities of PPO and POD were positively correlated with three tanshinones contents in roots, especially with Cryptotanshinone and Tanshinone I. Thus, proper amount of Mn fertilizer could improved obviously the quality of Salviae miltiorrhizae bunge.