A standard kε model was used to analyze the effect of row number and fin pitch on the flow and heat transfer performance of heat exchanger. The average heat transfer coefficients of each row of fin was given, and also the relationship between row number and j, f factors. It is found that the fin pitch is mainly related to air side pressure loss, and when the fin pitch is smaller than 2.5 mm, the air side pressure drop will be more sensitive to air velocity. The comprehensive performance of heat exchanger could be improved through the use of high thermal conductivity material in fins.