This paper analyzes the pore morphology of two different concrete mixtures (plain and fiber-reinforced) under two different curing conditions, through the use of a CT scanner and post-processing software. Twelve cylinders of 45.2 mm in diameter and 50 mm in height were cast. Half of the specimens were kept in a humidity-controlled room, at 20 °C and 60% humidity, and the rest in a curing room, at 20 °C and 100% humidity. All the specimens were scanned at the age of 28 days, using a micro CT scanner. The results reveal that the presence of fibers substantially modifies the pore morphology in the way of increasing the volume of voids and the pore-size, reducing the shape factor of the voids and reorienting the voids toward a direction more aligned to the one showed by the fibers. In general, the curing conditions do no exhibit a great impact on the results.