In response to the need of lightweight design in industries, composite materials are increasingly used to replace traditional metal tubes. However, subsurface defects such as voids, delaminations, and microcracks are still remaining common issues in composite pressure tubes. This paper introduces an application of digital shearography method in the nondestructive testing of high-pressure carbon fiber composite tubes. A new prototype high-pressure carbon fiber composite tube with a working pressure of 3000 psi is tested using digital shearography method. To detect the sub-surface defects, a reference shearographic phase map is created at 0 psi state, after that the composite tube is pressured to 120 psi using a water pump, then the second shearographic phase map is created at 120 psi state. By subtracting the two shearographic phase maps created in different pressure state, the sub-surface defects can be identified clearly. The shearographic NDT result is then compared with CT scan result. The Shearographic NDT fundamentals, optimization of shearographic NDT setup for high rigidity objects, experiment setup, and testing results are shown in detail in this paper.