The characteristics of condensation heat transfer of HFC245fa were investigated experimentally on horizontal tube bundles，which consist of 4-column and 5-row smooth tubes and enhanced tubes.All tubes in the test had the same equivalent outside diameter of 19.05 mm and effective length of 1000 mm.The water-side convection heat transfer coefficient of enhanced tube was obtained by modified Wilson plot method.The temperature difference between saturated vapor and cooling water was obtained by two-junction thermopiles (precision，±0.025℃) and the temperature difference of cooling water was obtained by thermocouples with small period standardization method (precision，±0.01℃).The effects of saturate temperature and heat flux on the condensation heat transfer were examined.The results show that the condensation heat transfer coefficients of HFC245fa on single smooth tube can be well predicted by Nusselt model under lower heat flux，but the deviation increases with the increase of heat flux.The heat transfer coefficient of single enhanced tube is 13.5 times that of smooth tube under the same heat flux.The coefficient of smooth tube bundle is higher than that estimated by Nusselt model (nearly 20%—50% according to row 2 to row 5).The condensation heat transfer of the enhanced tube bundle is sensitive to the quantity of condensate.The results may provide some guidelines for the design of shell-tube condenser for HFC245fa.