Three new diarylheptanoid glycosides, named (+)-S-myricanol 5-O-β-D-glucopyranoside, myricanene A 5-O-α-L-arabinofuranosyl(1→6)-β-D-glucopyranoside, and myricanene B 5-O-α-L-arabinofuranosyl(1→6)-β-D-glucopyranoside, were isolated from the bark of Chinese Myrica rubra, together with twenty known compounds. The absolute stereostructures of the new diarylheptanoid glycosides were elucidated on the basis of chemical and physicochemical evidence, including the application of the modified Mosher's method. The inhibitory effects of isolated constituents on the release of β-hexosaminidase from RBL-2H3 cells were examined, and several diarylheptanoids, myricanol, (+)-S-myricanol, myricanone, and myricanenes A and B, and a flavonol, myricetin, were found to show the inhibitory activity.