<jats:title>Abstract</jats:title><jats:p>Two novel flavanone glycosides, homoeriodictyol 7‐<jats:italic>O‐β</jats:italic>‐<jats:sc>D</jats:sc>‐[6‐(3‐hydroxybutanoyl)glucopyranoside] (viscumneoside IX; <jats:bold>1</jats:bold>) and homoeriodictyol 7‐<jats:italic>O</jats:italic>‐<jats:italic>β</jats:italic>‐<jats:sc>D</jats:sc>‐[6‐(3‐hydroxybutanoyl)glucopyranosyl](1→2)‐<jats:italic>β</jats:italic>‐<jats:sc>D</jats:sc>‐glucopyranoside (viscumneoside X; <jats:bold>2</jats:bold>), together with four known flavanoids, 2‐homoeriodictyol 7‐<jats:italic>O</jats:italic>‐<jats:italic>β</jats:italic>‐<jats:sc>D</jats:sc>‐glucopyranoside (<jats:bold>3</jats:bold>), viscumneoside I (<jats:bold>4</jats:bold>), viscumneoside III (<jats:bold>5</jats:bold>), and 4′,5‐dihydroxy‐3′‐methoxy‐7‐(2‐<jats:italic>O</jats:italic>‐<jats:italic>α</jats:italic>‐<jats:sc>L</jats:sc>‐rhamnopyranosyl‐<jats:italic>β</jats:italic>‐<jats:sc>D</jats:sc>‐glucopyranosyloxy)flavanone (<jats:bold>6</jats:bold>) were isolated from stems and leaves of <jats:italic>Viscum coloratum.</jats:italic> Their structures were elucidated on the basis of their NMR spectra, HR‐FAB‐MS data, and acid hydrolysis. Inhibitory effects of the four compounds <jats:bold>1</jats:bold>–<jats:bold>4</jats:bold> on the formation of osteoclast‐like multinucleated cells were investigated. As a result, all the four flavanoids showed significant inhibitory effects on the formation of osteoclast‐like multinuclear cells even at a low concentration of 2 μg/ml. The activities of <jats:bold>1</jats:bold>–<jats:bold>4</jats:bold> at such a concentration exceeded or approximated to that of elcitonin, the positive control drug at a concentration of 2 U/ml, suggesting that they may be of interest for the development of new anti‐osteoporosis drugs.