Human factors have been recognised as the primary causal factor among marine casualties over the last decade. Therefore, an attempt to identify the common Human and Organisational Factors (HOFs) between two relevant casualties as one of the countermeasures is proposed in this paper. The proposed marine casualty analysis method mainly consists of three processes, the “HOFs identification”, the “HOFs classification” and the “common HOFs screening” to constitute a systematic analytic procedure using Human Factors Analysis and Classification System for Maritime Accidents (HFACS-MA), which is based on Swiss Cheese Model. The first two processes devote to identifying the HOFs involved in individual accidents and the causation among them, and then to categorise those HOFs using HFACS-MA. Having these analysis outcomes, the third process can sieve out the common HOFs associating with two concerned accidents for setting up some proper countermeasures. By analysing two actual cases, this paper has shown that the common HOFs of the accidents can successfully be acquired and manifested via the analysis results of the third process. Those analysis outcomes can not only illustrate what and where the common HOFs are, but can also show how the common HOFs caused the defects of the organization (or system) within individual cases. The potential benefits that the proposed methodology can be acquired are demonstrated in the case study. Some considerations, including the limitations, regarding the proposed analytic method are also discussed and concluded at the end of this paper.