The present invention relates to the field of CT tubes, and discloses a tube core over-temperature protection device for a CT tube, comprising an outer sleeve of a tube core body, a circulation conveying component, an
oil cooling and heat dissipation component, and a
water cooling and heat dissipation component. The tube core body is provided with a
cathode filament and a rotating
anode, the outer sleeve is arranged outside the tube core body for protecting the tube core body, and the circulation conveying component is installed outside the outer sleeve for conveying
transformer oil in a
transformer oil cavity. Compared with the prior art, the present application realizes circulation cooling of
transformer oil by arranging a circulation conveying component and an
oil cooling and heat dissipation component when the tube core body is in normal operation. When the detected temperature exceeds a safe range, a warning light will display a yellow light, and a sound will be generated for reminder, and the rotation speed of an
oil pump and a cooling fan will be increased to accelerate the circulation of
transformer oil and accelerate the heat dissipation by blowing air, thereby preventing the
transformer oil from heating up too fast.