Passive intermodulation (PIM) in communication systems is an unwanted interference caused by weak nonlinear current-voltage characteristics of radio frequency (RF) passive components. Characterization of PIM is important for both the study of PIM mechanisms and the location/suppression of PIM sources. PIM probes, made of open-ended coaxial transmission lines, have almost the same coupling strength to carriers and PIM products, and are usually used for near-field PIM characterization. Namely, it doesn’t have any filtering capability. Therefore, it cannot stop the carrier power from entering into PIM tester’s receiver, which may trigger active intermodulation of the receiver and degrade the PIM tester’s performance. To overcome this drawback, a passive filtering coaxial probe is proposed here. Compared with existing passive coaxial PIM probes, it has stronger coupling strength for PIM products than for carriers. Thus, the probe itself can block part of the carrier power entering into the PIM tester’s receiver. This advantage helps improve PIM tester’s overall performance. Both theoretical analysis and experiments are conducted for demonstration. The proposed probe brings more possibility to PIM characterization.