During the summer months of 1967 the author observed the mass stranding of an octopus, Tremoctopus violaceus Delle Chaje, upon the beaches of northern Kyushu (Fig. 1 & Table 1). This epipelagic octopus was considered as the southern element such as baloonfish and some squids (Thysanoteuthis rhombus, etc.) which were transported in summer by the Tsushima Current into the Japan Sea and sometimes stranded upon the beach in winter season. On these beaches, so far, the octopus had been also seen in the cold season (Fig. 2 & Table 2). This paper deals with some notes on the unexpected mass appearance of the animals in that summer. The octopus was stranded upon the beaches between Karatsu and Tsuyazaki from the early August to the early September (Fig. 1 & Table 1). The prominent phenomenon was seen in the end of August in the whole area, and at the beach of Ainoshima the stranded octopus were counted as many as some 300 individuals on 27th of the month. Most of them were young individuals less than 35 cm in total length (Table 1). This tendency was regarded as characteristics for the summer group in contrast to the winter one which were composed of adults more than 60 cm (Fig. 2). These mass strandings of the octopus were supposed to be caused by the larger transportation of the animals by the Current, which might be presumed to be due to the more forcible Current in this summer than in a common one. Another fact supporting this supposition was the first summer stranding ever recorded on Tsuyazaki of the squid, Thysanoteuthis rhombus Troschel, belonging to the same ecological group as the octopus (Table 1).