A wavelet multi-resolittion cross-correlation analysis was developed and applied to experimental pressure-time signals in order to analyze the characteristics of swirling gas-solid flow in both Fourier and physical spaces. The experiment it-as carried out in a horizontal pipe with a length of 7.5 m and an inner diameter of 76 mm. The initial swirl number based on the total inflow was varied from 0.0 to 0.61, the mean gas velocity was varied from 6 to 28 m/s, and the solid mass flow rate was varied from 0.08 to 0.5. From the wavelet multi-resolution correlation analysis of the fluctuating pressure in the range of low air velocity, the characteristics of swirling gas-solid two-phase flows were exit-acted at various frequencies. Much stronger correlations were found in the range of low frequency, which implied periodic motion of dunes and sliding clusters. Additionally, it was revealed that the motion of a large cluster sliding flow contains two smaller clusters and the moving velocities of dimes were I m/s and 2 m/s, respectively. However, no correlation existed at Smaller scales of correlation features, which indicated heterogeneous suspension flow.