Abstract: A tubular exchanger for 1kW Stirling generator is designed in this paper.The tubes of the heater are composed of 288 stainless steel tubes with outer diameter of 2.0 mm,wall thickness of 0.4 mm and length of 40.0 mm.The arrangement of the tubes is misarranged,the center distance between two tubes is 3.0 mm,and the end face of each tube is connected to the end face of the cooler by laser welding.The total heat transfer coefficient of the tube is 2.38107 kW/(m²·K);the total heat exchange of the cooler is 5.85 kW when the logarithmic mean temperature difference is 45.3 K;the pressure drop in the tube is 373.0 Pa;by laser welding,the pressure resistance of the tubes is not less than 5.0 MPa,and the leakage rate is lower than 5.0×10^-5Pa·m³/s.This design meets the design requirements of the heater of 1 kW Stirling generator.