New method for preparing cyclopentanediol from bicyclic ketal is described. Bicyclic ketal is cleaved to give 1,5-diketone, which is then reductively coupled intramolecularly to yield 1,2-cyclopentanediol. A solution of bicyclic ketal (1a) in methylene chloride was treated with aluminum chloride(2 eq.)-sodium iodide(l.5 eq.) at ambient temperature for 3 h to give the 1,5-diketone (2a) in 71% yield after basic work-up followed by short path column chromatography. A solution of the 1,5-diketone (2a) in THF was reacted with titanium tetrachloride(6 eq.)-Mg(Hg)(0.3 eq.) at $0^{circ}C$ for 4 h to give the 1,2-cyclopentanediol (3a) in 75% yield after basic work-up followed by short path column chromatography.