The utility model discloses a high pressure heat exchanger seal structure mainly comprises flange, omega becket gasket, linear sealing groove and line seal gasket, the flange is two of setting up in pairs, and omega becket gasket is two of setting up in pairs, and every omega becket gasket welds with a slice flange respectively mutually, and two omega becket gaskets are with sealed facial featureslaminating, through its outer fringe welding together, the intra -annular space of omega becket gasket constitutes confined space, on the sealed face of a slice omega becket gasket was wherein located in the linear sealing groove, the line seal gasket who locates the linear sealing inslot formed the linear sealing in the sealed face department of two omega becket gaskets. The utility model discloses the sealed of high -pressure heat exchanger and hydrostatic test hydrops problem have been solved to the seal structure good reliability, though tube journey pressure or (with) the temperature hasthe fluctuation, also has fine sealed effect, can guarantee the operation of equipment safe and reliable.