An assembly-type casket having a reduced number of visible joins and cuts in the board material as viewed after assembly and improved finish, which enables joins (engagement grooves and engagement protrusions) between folding side boards and insertion end boards to be more readily produced and good join strength to be maintained. A casket (10) having basic side boards (12B) on the left and right long sides of a bottom board (12A) and basic end boards (12C) on the front and rear short sides thereof. Folding side boards (12X) are provided on the upper side of the basic side boards (12B) and insertion end boards (12Y) are joined to the front and rear outsides of these boards (12C, 12B, and 12X). Lower engagement protrusions (17) and upper engagement protrusions (18) are provided in the front and rear end surfaces of the basic side boards (12B) and the folding side boards (12X). Engagement grooves (16) (fig. 6) that can be slide-inserted into these protrusions (18, 17) are provided in the side end sections of the inside surfaces of the insertion end boards (12Y). Gap sections (19a) are provided above the upper engagement protrusions (18) and covering sections (19b) (fig. 6) that fit into the gap sections (19a) are provided above the engagement grooves (16).