Chemical and microbiological properties of Makgeolliafter high hydrostatic pressure (HHP) treatment were investigated to determine the possibility of shelf-life extension. Laboratory prepared Makgeolliwas treated with 400MPa for 5 min and stored for 6 days at 25°C and chemical and microbial properties were analyzed. On day 6 the alcohol content of untreated Makgeolliwas 8.27%, whereas HHP-treated showed 7.50%, and pH were 2.76 and 3.22, respectively. Titratable acidity of HHPtreated Makgeolliwas increased by less than 0.1%, whereas the untreated was increased by more than 0.3% on day 6. Reducing sugar content, on the other hand, increased continuously in HHP-treated Makgeolli, and reached to 2.43% by day 6, but decreased to 1.13% in untreated Makgeolli. In HHP-treated Makgeolli, yeast was reduced to below detection limit and grew again on day 6. Lactic acid bacteria were also reduced by HHP, but reappeared within 2 days at the level of 1-2 logs CFU/mL. HHP slowed down the chemical changes such as pH, titratable acidity, and alcohol content; thus showing HHP treatment can be used to extend the shelf-life of Makgeolliby inactivating lactic acid bacteria and yeast.