In this study we present a microwave sensor based on the quadratic-shape and designed for detecting glucose concentration in aqueous solutions by using a microwave near-field electromagnetic interaction technique. We found a linear relationship between the microwave reflection coefficient of the suggested system and the concentration of glucose in solution. Due to this linear relationship we were able to determine the glucose concentration in the range of 0–250 mg/dL at an operating frequency near 3.6 GHz. The measured minimum detectable signal was 0.0044 dB/(mg/dL) and the measured minimum detectable concentration was 6.8 mg/dL. These results suggest that the system we offer has a high enough accuracy for non-contact glucose monitoring and provides a promising basis for developing a non-invasive glucometer.