Abstract: This study employs a combined approach of close-in explosion impact testing and quasi-static comparison testing to investigate the effect of explosion impact loading on the aseismic performance of concrete-filled double-layer steel tube piers made of engineered cementitious composites (ECC) concrete. A close-in explosion test using 2.0 kg TNT was conducted on the pier. The test results showed that the pier maintained its overall structural integrity after the blast impact, with no significant visible damage observed. Strain monitoring data indicated that the strain values of both the inner and outer steel tubes had significantly exceeded the yield strain of steel tubes. Displacement measurements revealed that the specimen had developed a residual displacement of 1.461 mm at the height directly opposite the blast epicenter. Further quasi-static comparative tests were conducted between the post-explosion specimen and an intact specimen. The test results revealed that the hysteresis curves of the specimen subjected to explosive impacts exhibited pronounced pinching patterns. The calculations of cumulative energy consumptions and of equivalent viscous damping ratios indicated a general reduction in its energy dissipation capacity. The skeleton curves of both specimens indicated that the pier retained excellent load-bearing capacity and significant post-yield stiffness. Notably, the post-explosion specimen exhibited a unique phenomenon of positive load strengthening, with positive residual deformation appearing after the ninth loading stage. This confirmed that the explosive impact significantly altered the structural mechanical response mode. The damage index D for this specimen after close-in explosion was calculated to be 0.202. This degree of damage was within the repairable range and approaches the limit for immediate serviceability without a repair. This series of tests demonstrates that the concrete-filled double-skin steel tube piers filled with ECC maintain its core load-bearing capacity after undergoing close-in blast impacts. Although its aseismic performance has shown some degradation, their overall performance still remains sufficient to meet normal service requirements.