The invention discloses a transformer vacuum on-load tap-changer electrified oil sample taking device. The transformer vacuum on-load tap-changer electrified oil sample taking device comprises an oil pump, wherein the oil pump is at least connected with an oil pumping tubing with a first switch valve, and an oil return pipe with a fourth switch valve; a first connecting pipe with a second switch valve is connected with the oil pumping tubing in a bifurcate mode, and the oil pumping tubing is used for connecting the first switch valve with the oil pump; a second connecting pipe with a fifth switch valve is connected to the oil return pipe in the bifurcate mode, and the oil return pipe is used for connecting the fourth switch valve with the oil pump; a third switch valve and a sixth switch valve are respectively connected between the first connecting pipe and the oil pump as well as between the second connecting pipe and the oil pump in series; the oil pump is arranged in a portable oil extraction box body; the oil pump is connected with the oil pumping tubing by an oil intake connecting hose, and is also connected with the oil return pipe by an oil discharge connecting hose. The transformer vacuum on-load tap-changer electrified oil sample taking device has the characteristics of simple structure, using convenience and reliability, capabilities of obtaining actual oil samples under the condition of no power failure of a transformer without affecting the running of an on-load tap-changer and the like.