A glow plug electrification control apparatus which can maintain the same heater temperature even when resistance varies among glow plugs to be used, and a glow plug electrification control system using the same. The apparatus (101) includes temperature-raising-period-resistance acquisition means for temperature-raising-period resistances Rg1(0.5), etc. of glow plugs (GP1-GPn) at predetermined timings during a temperature-raising period; maintaining-period electrification control means for maintaining the heater temperature Tg1(t), etc. at predetermined target temperatures Tm1, etc. after the temperature raising; and maintaining-period resistance acquisition means for acquiring maintaining-period resistances Rg1(t), etc. of the glow plugs GP1, etc. in a maintaining period.