The utility model relates to a reactor equipment state technical field refers in particular to a high pressure parallel reactor iron core vibration measuring device and methods of measurement, reactor iron core, optic fibre vibration sensor, fiber coupler, fiber grating including locating on the transformer tank mediate appearance and computer, and the reactor iron core corresponds the setting with optic fibre vibration sensor, and optic fibre vibration sensor connects in fiber coupler, and fiber coupler connects in fiber grating mediation appearance, and fiber grating mediates the appearance and connects in the computer. The utility model discloses a when the reactor moves, reactor iron core oscillation generation to reach fiber coupler with the vibrational force through optic fibre vibration sensor, rethread fiber coupler reaches fiber grating and mediates the appearance, and the rethread computer reachs measuring result, and is very accurate, effectively masters the characteristics of reactor iron core vibration.