The invention discloses an eddy current testing system for nondestructive testing of a pipeline, which belongs to the field of nondestructive testing technology. The eddy current testing system comprises a data processing unit, a first signal conditioning unit, a second signal conditioning unit, and a testing probe, wherein the testing probe comprises an excitation coil, a receiving coil, and a passive resonance coil; and the passive resonance coil is arranged between the excitation coil and the receiving coil. According to the invention, no more magnetizing treatment device is needed for testing, so that the system volume is greatly reduced, thereby reducing the requirement of the testing system of the invention on cleanliness inside the pipeline, improving flexibility of equipment in the pipeline of the testing system, and greatly reducing the system cost; and by introducing the passive resonance coil between the excitation coil and the receiving coil, the coupling between the excitation coil and the receiving coil can be enhanced, thereby significantly improving the energy transmission efficiency, further improving the sensitivity of the testing probe so that the probe can accurately test pipeline defects at a higher lift-off height, and improving the defect detection capability of the probe.