A bicycle chain connecting link comprises a link pin and a link plate. The link pin has a center axis and comprises a main-body, a head portion, and an intermediate portion. The intermediate portion has an outer diameter smaller than an outer diameter of the main-body and than an outer diameter of the head portion to define a groove between the main-body and the head portion. The link plate comprises an elongated opening to which the link pin is removably attached. The elongated opening comprises an insertion opening and an attachment opening connected with the insertion opening. The guiding portion includes a sliding surface slidable with the head portion. The protrusion is provided between the insertion opening and the attachment opening and protrudes from the sliding surface to be slidable with an outer periphery of the head portion.