Abstract: A hot press roller has an outer pipe, an inner pipe inserted in the outer pipe, an annular separator disposed in a first end of the outer pipe, a separation ring disposed in a second end of the outer pipe, a round center hole formed on the annular separator, a circular center hole formed on the separation ring, a first end of the inner pipe passing through the round center hole, a second end of the inner pipe passing through the circular center hole, a water outlet tube connected to the first end of the inner pipe, and a water inlet tube connected to the second end of the inner pipe. A first safety valve is disposed on the annular separator. A second safety valve is disposed on the separation ring. A cooling agent filling tube is disposed on the separation ring.