Non-destructive characterization of fuel tube of compact high temperature reactor was carried out using quantitative X-ray computed tomography (CT). The fuel tube is made of graphite and parameters of its fuel/coolant channels such as area, inter-spacing and longitudinal uniformity need to be characterized properly throughout its length to ensure homogeneous temperature distribution. A prototype fuel tube was fabricated and characterized using X-ray-CT at two different resolution scales followed by quantitative image analysis. The study reveals potential of X-ray CT in detecting small scale and large scale uniformity of fuel tube channels qualitatively and quantitatively.