Due to their inherent structural characteristics, masonry structures are prone to hidden damage, such as voids. Hidden damage that accumulates over time poses a threat to the safety of the structure. Non-destructive testing (NDT) technology has gained popularity in the field of detection. NDT techniques are effective tools for detecting hidden damage in masonry structures. However, there is an incomplete understanding of hidden damage, and confusion still exists regarding the selection of suitable NDT method. Therefore, in this paper, the application and research directions of Non-Destructive Testing (NDT) in civil engineering at this stage are summarized through bibliometric analysis. It has been found that integrated methods and intelligent techniques are effective ways to detect hidden damage in masonry structures.