Abstract: The depletion test for the condensate gas in gas condensate reservoir is usually done in PVT cell without considering the influence of porous media，but in real reservoir，the change of fluid phase behavior occurs in porous media.By means of long core test，the depletion performance of condensate gas system in porous media is studied，and the comparison with the depletion in PVT cell is carried out.Study indicates that the condensate gas rich in oil condensate depletion performance is different with PVT test result，average oil-gas ratio is different under different pressure in different depletion speed，the higher the speed is，the lower the recovery of oil condensate is，and the greater the average oil-gas ratio.The oil condensate recovery in long core is higher than that in PVT cell，but there is only a little difference for natural gas recovery.It is strongly suggested that core depletion test is used to study retrograde condensation performance feature in gas condensate reservoir depletion production.

Key words: gas condensate reservoir, phase behavior, porous medium, long-core flooding, depletion