The utility model relates to a brake plate inching toothed-disc braking safety device for an oil pumping unit. The brake plate inching toothed-disc braking safety device comprises a safety mechanism, wherein the safety mechanism comprises a brake plate and a toothed disc which is connected with a brake wheel or a brake hub. The brake plate inching toothed-disc braking safety device is characterized in that triangular teeth are uniformly distributed on the outer circle circumference of the toothed disc; the brake plate is provided with a brake plate tooth which is meshed with the triangular teeth of the toothed disc; the brake plate is provided with an elongated slot; a reset spring is arranged in the elongated slot; a brake plate shaft is connected into the elongated slot in a sliding way; the brake plate shaft can be fixedly connected with a reduction gearbox by adopting a lengthened brake shoe axle or through an axle seat; the elongated slot, the reset spring and the brake plate shaft on the brake plate construct a brake plate axial inching mechanism. The brake plate inching toothed-disc braking safety device has the beneficial effects that a safety function can be realized by engaging or disengaging a brake fuse in a way of shaking an operating mechanism handle; an operator stands at a safety position relative to the oil pumping unit, so that the safety is ensured; the brake plate can move slightly along the brake plate shaft to realize automatic alignment and meshing with the toothed disc, and easiness, convenience and rapidness in operation are realized.