This study presents zinc oxide (ZnO) microstructures encapsulated in a poly(dimethylsiloxane) (PDMS) polymer matrix for the fabrication of a flexible mechanical load sensor. The resistance and capacitance properties of the ZnO-PDMS membrane in the presence of mechanical load in the range of 0–500 g have been studied using electrochemical impedance spectroscopy. The obtained impedance spectra reveal a decrease in active resistance (R) with increasing load mass. This decrease is attributed to an increase in contact area between the ZnO crystals and the upper electrode, leading to enhanced conductivity of the ZnO-PDMS membrane. Apart from the resistive response, the sensor exhibits capacitive response. The volume fraction of ZnO and PDMS in the membrane has been estimated, and the electrical capacity of the sensor has been determined. The obtained results are found promising for fabrication of various applications in sensing, human health diagnostics, and wearable electronics.