Abstract: Provided is a permeability spectrum testing device and method for a micron-sized sample based on a near-field microwave probe. The permeability spectrum testing device for a micron-sized sample based on a near-field microwave probe includes the near-field microwave probe, a vector network analyzer (VNA), and a control system that are connected sequentially, where the near-field microwave probe includes a microwave probe tip having a signal terminal and a ground terminal shorted; the near-field microwave probe is connected to the VNA to form an impedance loop; when the target sample is tested, an impedance of the impedance loop changes, followed by a change of a scattering parameter (S-parameter) of the VNA; and the VNA is configured to receive reflected signals detected by the near-field microwave probe in four states, obtain S-parameters in the four state, and determine a permeability spectrum of the target sample.