A degradable cardiac pacing current-providing wire, comprising: conductive core; insulating film ,covering said conductive core, wherein said conductive core is made of magnesium alloy, the weight percentage of said magnesium alloy is: zinc 4.5-5.5%, manganese 0.8-1.2%, calcium 0.8-1.2%, and the remainder is magnesium, said insulating film is made of either or at least two copolymers of Polylactic acid (PLA), Polyglycolic acid (PGA), Polycaprolactone (PCL), Polydioxanone (PDS) and Polyhydroxyalkanoate (PHA). A cardiac pacing current-providing unit, for use in providing pacing current to the heart of the patient, comprising: wire; suture needle and connecting electrode which is connected to the cardiac pacemaker, there is no wire residue in the body after degradation, and no metal artifacts will occur, which makes the patients free from the need for re-operation, and reduces the mental, physical and economic burden caused by the operation, has a strong clinical application value.