With the advent of X-ray micro-computed tomography which is now routinely used, pore-scale fluid transport and processes can be observed in three-dimensional (3D) at the micro-scale. Multiphase flow experiments that are conducted under $i\mathrm{}n\mathrm{}s\mathrm{}i\mathrm{}t\mathrm{}u$ imaging scanning conditions can be utilized to study the pore-scale physics relevant to subsurface technological applications. X-ray micro-tomographic imaging is a non-destructive technique for quantifying these processes in 3D within confined pores. This paper presents a review for the usage of X-ray micro-computed tomography experiments to investigate wettability effect on multiphase flow. The fundamental workflow of combining experiments with pore-scale $i\mathrm{}n\mathrm{}s\mathrm{}i\mathrm{}t\mathrm{}u$ imaging scanning such as equipment requirements, apparatus design and fluid systems are firstly described. Then imaging analysis toolkit is presented for how to quantify interfacial areas, curvatures, contact angles, and fluid properties through these images. Furthermore, we show typical examples, illustrating recent studies for the wettability characterization by using X-ray micro-computed imaging.