A combined coffin structure comprises a base, two long side plates and two short side plates, two first fixings, two second fixings and four supporting members.The base has a rectangular fixing groove, one side of the two long side plates and one side of the two short side plates are correspondingly provided with two long side walls of the base and two short side walls of the base forming the rectangular fixing groove.The two first fixings are arranged at one end of the two long side plates far away from the base, and the two ends of the first fixings and the long side plates are respectively provided with a first interval； the two ends of the second fixings and the short side plates are respectively provided with a second interval.Each supporting member includes two plates which are connected with each other. The two plates of each supporting member are used to fix the long side plate and the short side plate adjacent to each other, and each supporting member is corresponding to the outer wall of each long side plate and the short side plate.一種組合棺木結構包括：底座、兩個長側板及兩個短側板、兩個第一固定件、兩個第二固定件與四個支撐件。底座具有矩形固定槽，兩個長側板的一側及兩個短側板的一側對應設置於形成矩形固定槽的兩個底座長側壁及兩個底座短側壁。兩個第一固定件設置於兩個長側板遠離底座的一端，且各第一固定件與其所設置的長側板的兩端分別具有第一間隔：各第二固定件與其所設置的短側板的兩端分別具有第二間隔。各支撐件包含有兩個彼此相連的板件，各支撐件的兩個板件用以固定彼此相鄰的長側板及短側板，且各支撐件對應位於各長側板及各短側板的外側壁。
