Objective To design a wearable multi-frequency electrical impedance tomography (mfEIT) system for regional lung ventilation analysis and to preliminarily evaluate its feasibility for acquiring regional relative ventilation information in a lung ventilation model and under wearable conditions.Methods A 16-electrode wearable mfEIT system was developed based on a Cortex-M7 microcontroller. Multi-frequency sinusoidal excitation signals were generated using a wideband mirror constant current source, and boundary voltages were acquired through a high-speed differential acquisition circuit. The voltage signals were preprocessed using target-bin discrete Fourier transform (DFT) demodulation and fourth-order infinite impulse response (IIR) low-pass filtering and were then transmitted to a personal computer (PC) via Bluetooth. EIT image reconstruction was performed using EIDORS. Relative ventilation signals were further extracted from the region of interest (ROI), and relative flow-volume loops were constructed to describe dynamic changes in regional lung ventilation. A lung ventilation model experiment was conducted to assess the signal acquisition performance, normalized lung volume parameter extraction, and the identification of uneven ventilation between the left and right lungs. Both matched ventilation and left–right uneven ventilation conditions were established to examine whether the reconstructed images and regional signals could reflect controlled differences in ventilation distribution. A continuous acquisition demonstration under wearable conditions was further performed by a single healthy participant to observe the ability of the system to continuously record relative ventilation changes in a practical wearable setting.Results The system achieved multi-frequency excitation over a range of 1 kHz to 500 kHz. The maximum aggregate acquisition rate of complete boundary-voltage frames was 40 fps, with each complete frame comprising 208 valid voltage measurements acquired at one excitation frequency. Under four-frequency frame-by-frame scanning, the effective acquisition rate was approximately 10 fps for each excitation frequency. Under a 1 mA excitation current, the average signal-to-noise ratio (SNR) remained above 42 dB within the 500 kHz excitation bandwidth, and reached 61.4 dB at 180 kHz. The total voltage fluctuation during continuous acquisition was less than 1%. These results indicated that the system maintained stable boundary-voltage acquisition performance over a wide excitation-frequency range and during continuous operation. In the lung ventilation model experiment, the errors of normalized tidal volume, normalized inspiratory reserve volume, and normalized expiratory reserve volume extracted by mfEIT were 5.24%, 10.31%, and 9.29%, respectively, compared with the bidirectional flowmeter measurements. In the uneven ventilation between the left and right lungs, the relative vital capacity of the right lung measured by EIT was 54.76% of that of the left lung, with an error of 3.53% compared with the flowmeter result. The single-participant wearable demonstration showed that ventilation-related signals could be continuously acquired at the different excitation frequencies and that changes in relative tidal volume, respiratory cycle, and relative flow-volume loop morphology could be tracked during sitting, light exercise, and standing. These observations were descriptive and did not establish diagnostic accuracy or absolute pulmonary-function quantification.Conclusion The developed wearable mfEIT system integrates wideband excitation, rapid boundary-voltage acquisition, embedded signal processing, wireless transmission, EIT reconstruction, and ROI-based functional analysis within a compact platform. Its main contribution is the establishment of an end-to-end pathway that converts multi-frequency electrical measurements into interpretable regional relative ventilation information, enabling ventilation distribution and temporal dynamics to be considered within a unified framework. The model results support the identification of regional ventilation differences, while the single-participant experiment demonstrates the feasibility of continuous wearable acquisition. The system therefore provides a technical basis for continuous regional relative ventilation monitoring. Further comparisons with standard pulmonary-function measurements and reference EIT systems in larger populations are required before clinical assessment or absolute regional pulmonary-function quantification can be considered.