Abstract: The immediate heat exchanger (IHX) is the key component to connect the high-temperature gas-cooled reactor with the helium turbine for high-temperature gas-cooled reactor coupled with indirect gas turbine cycle (indirect HTGR-GT) system. IHX transfers the high temperature energy generated by reactor to gas turbine loop. IHX can reduce the difficulties of the design, operation and maintance of helium gas turbine. On the other hand, IHX will lower the cycle efficiency due to IHX’s heat transfer and pressure loss. So the characteristics of heat transfer and pressure loss, material performance, compactness should be considered for the design and the choice of IHX because of its special operating conditions. The features of printed circuit heat exchanger (PCHE) and its feasibility in the indirect HTGR-GT were discussed. The characteristics of heat transfer and pressure loss of the PCHE were studied and the factors effecting heat transfer efficiency and pressure loss were analyzed. Furthermore, the measures to improve the performance of the IHX were presented.