During application of D-glucose-u-14C paromomycine II is higher labelled and shows a different dependence on the application time than paromomycine I, which is isomer at the paromose part. For the two paromose isomeres different rates of synthesis are supposed that change nonproportionally to each other. The distribution of radioactivity in paromomycine I shows that there is no fragmentation of the glucose chain during the biosynthesis of glucosamine, ribose, and paromose I. As to the 2-deoxystreptamine the result has not been ascertained.