<p>An all-solid-state microsensor for metformin was developed utilizing a molecularly imprinted polymer (MIP). In the polymerization process, ethylene glycol dimethacrylate (EGDMA) was used as the crosslinker, while metformin and methacrylic acid were used as the template and functional monomer, respectively. The metformin-imprinted polymer was integrated into a polyvinylchloride (PVC)-membrane matrix to act as the ionophore. The microsensor exhibited a near-Nernstian response over the concentration range of 10⁻⁶ to 10⁻¹ mol L⁻¹, with a slope of 56.5 ± 1.9 mV/decade (R²: 0.999) maintained consistently over an operational period of eight weeks. The detection limit of the microsensor was calculated to be 9.23 × 10⁻⁷ mol L⁻¹, with an optimal operating pH range of 4.0–7.0 and a fast response time of less than 10&#xa0;s. The microsensor also exhibited excellent selectivity against common interfering species. The developed microsensor was successfully applied to the determination of metformin in commercial drug samples. The potentiometric data showed strong agreement with UV-Vis spectroscopic results, confirming the accuracy and analytical reliability of the method.</p>