An implantable medical instrument is made of an iron-based alloy, comprising an iron-based alloy substrate and a drug-loaded coating. The drug-loaded coating comprises a polymer and an active drug； the weight average molecular weight of the polymer is greater than or equal to 50,000 and less than or equal to 1,000,000； micro-pores having a diameter of less than or equal to 10 micrometers are formed in the drug-loaded coating； the percentage of the active drug released on the implantable medical instrument made of an iron-based alloy is greater than or equal to 4t1/2−；1 and less than or equal to 6.9t1/2+63, wherein t ∈； (0, 28], and t represents sampling time/days.
