Four enantiomerically pure new α-tetralones, (4S)- and (4R)-5-hydroxy-4-methoxy-α-tetralones and (4S)- and (4R)-5,8-dihydroxy-4-methoxy-α-tetralones were isolated, together with five known ones, (4S)- and (4R)-4,8-dihydroxy-α-tetralones, (4S)-4,8-dihydroxy-5-methoxy-α-tetralone and (4S)- and (4R)-4-hydroxy-α-tetralones, from the fruit of Juglans mandshurica MAXIM. var. sieboldiana MAKINO. Their structures were established on the basis of spectral analysis. To the best of our knowledge, this is the first isolation of the (4R)-4-hydroxy-α-tetralone derivative from Juglans species.