Microwave sensors are very promising for sensing the blood glucose levels non-invasively for their non-ionizing nature, miniaturized sizing, and low health risks for diabetics. All these features offer the possibility for realizing a portable non-invasive glucose sensor for monitoring glucose levels in real time. In this article, we propose a triple poles complementary split ring resonator (CSRR) produced on a FR4 substrate in microstrip technology in the cm-wave band (1-6 GHz). The proposed bio-sensor can detect the small variations in the dielectric properties (relative permittivity and dielectric losses) of glucose in the blood mimicking aqueous solutions due their intense interaction with the electromagnetic field at harmonic resonances. The resonator exhibits higher sensitivity performance at the different resonances compared to the single and double-poles counterparts as demonstrated by simulations in a 3D full-wave EM solver.