To design a chain conveyer so as not to shift in a lateral direction and move, and so as to be easily cleaned.

A crest portion 9 which is off-center about a virtual surface vertical to a center line of a crown is equipped to each cog 3 on only back wall 10, and the crest portion 9 is inserted between projecting portions of a link forming a chain. The layout of the crest portion 9 is trapezoidal and has isosceles sides, is converged toward the cog 3, and has a recessed lateral direction surface. Therefore, the lateral direction surface is joined with a border surface of a surface 10 of the cog 3, and has no sharp edge. Consequently, for example, by spraying water, the crown is easily cleaned.