Due to the low gas price, production of liquid oil has attained more attention. Producers are seeking to maximize liquid oil production from gas-condensate reservoirs. However, once a shale gas-condensate reservoir is produced, by reservoir depletion, the pressure near the well will decrease below the dew point pressure because of its ultra-low permeability. Then liquid condensate forms. The liquid condensate accumulates near a wellbore forming condensate banking, thus gas productivity is decreased. And the low-saturation condensate in the formation could remain unproduced. To solve the above problems, this paper proposes huff-n-puff gas injection to boost the reservoir pressure near the production wells. It is expected that the pressure increase during the huff period will "vaporize" the liquid condensate which will be produced during the puff period. Experiments were conducted to investigate this mechanism. In the experiments, a core was initially saturated with a gas-mixture. Then huff-n-puff cycles were repeated. The CT scanner was used to analyze the fluid distribution in the core, and by using CT numbers, saturation of condensate would be determined. The effects of these parameters were studied: 1) huff-n-puff cycles, 2) soaking time. The experimental results showed that the vaporization mechanism could reduce the liquid dropout. The results also show that injection pressure does not significantly change oil recovery when the pressure was higher than the dew point pressure, and soaking time slightly affect condensate recovery. The experimental results indicate that huff-n-puff gas injection could be an effective approach to enhance gas-condensate recovery in shale gas reservoirs.