The present paper deals with reproductive features in the following twelve species in eight genera of articulated coralline algae in Japan: Amphiroa zonata, Bossiella cretacea, Marginisporum crassissimum, Alatocladia modesta, Calliarthron yessoense, Serraticardia maxima, Corallina kaifuensis, Corallina officinalis, Corallina pilulifera, Corallina sessilis, Corallina sp. (resembling Haliptylon squamatum in external appearance) and Jania nipponica. All types of reproductive structures were studied morphologically in each species except in Marginisporum crassissima and Jania nipponica where only sporangial plants were observed. The formation of conceptacles and the development of reproductive organs agree in most respects with previous reports on other related coralline taxa. Information on reproduction is given for the first time for Amphiroa zonata, Alatocladia modesta, Corallina kaifuensis, Corallina pilulifera, Corallina sessilis, Corallina sp. and Jania nipponica. The process of paraphysis formation in spermatangial conceptacles of the Corallinaceae is described for the first time.