Abstract: The computer emulation of performance experiment system has been done for the condensers which adopt frequence-convertible compressor and a second working-fluid calorimeter. The emulation software can run in Windows 98/2000 environment This software has been used to do the experimental performance prediction of air-cooling condenser and water-cooling condenser. The results reflect the peculiar performance of the condensers. It can greatly decrease the experiment work and shorten the trial-manufacture period of condenser.