The conventional pressure change method used in leakage tests is sensitive to the ambient temperature variation. We propose a new method using a correlation technique to compensate for temperature variation in pressure change leakage detection. In the proposed method, gas within a vessel is compressed in such a sequence that it shows no correlation with the ambient temperature variation. The extent of leakage is estimated from the correlation between the pressure variation in the vessel and the compression sequence signal. Experimental results showed that leakage can be successfully detected by the proposed method without being affected by temperature variation.