The characteristics of soil liquesfaction were investigated using the H/V rations of microtermors in the Yuan-Lin area. Liquefaction at Luen-Ya-Li, Yuan-Lin in central Taiwan was clearly observed with serious sand boils bringing about massive damages during the Chi-Chi earthquake. Based on the H/V ratios calculated from microtremor measurements at 42 points distributed in this area, the predominant frequencies appeared between 0.8-0.9 Hz for the liquefied area, with higher relative amplification factors compared to other areas. In the study, the ground vulnerability index (Kg) values (Nakamura 1996) in the liquefied areas were higher than those in the neighboring areas without liquefaction. This study shows supporting evidence for the first time that the H/V ratios of microtremors can be a good alternative indicator for an area's potential for liquefaction.