In this article, we report the complete genome sequences of Massilia sp. strains B-10 (RCAM05335) and H-1 (RCAM05339), which were isolated from the water of the Dal'nee Verkhnee Lake in the Shulgan-Tash cave in Russia (53°2'0″N, 57°3'0″E). The sequences were obtained using an Oxford Nanopore Technologies MinION system.