Near-field scanning microwave microscope (NSMM) is a powerful tool for characterization of the dielectric, electric, and magnetic properties of solid surface and subsurface, at the micro-and nano-scales.NSMM technique has also been applied to detect softmaterials and live organisms.Recently, we have developed a homemade NSMM system and demonstrated its capability in detection of subsurface structures in sealed micro-fluidic systems by using a high-quality factor resonator.This is realized by measuring the magnitude and frequency shift of the reflection parameter S11 with a standard microwave network analyzer.