Hardaliye, a traditional non-alcoholic beverage, made from red grape pomace from wine production and produced by lactic acid fermentation with addition of different concentrations of whole/ground or heat-treated mustard seeds and of sour cherry leaves. Short shelf life of hardaliye limits its consumption and search in trend to process hardaliye to extend its shelf life. Thus, high hydrostatic pressure treatment of hardaliye drink with determination of changes in physicochemical and sensory properties in addition to microbial inactivation were studied according to Box-Behnken design. Maximum 5.10±0.00, 4.21±0.00, 5.38±0.59 and 5.05±0.22 log reductions were obtained in total mesophilic aerobic bacteria, total mold and yeast, Brettanomyces bruxellensis and Lactobacillus brevis by HHP. Shelf-life studies of the hardaliye samples were conducted with optimum processing parameters of 490 MPa, 29 oC for 15 min with the response variables of OD520 and inactivation of L. brevis. Both control and HHP treated samples were stored at 4 and 22 C for shelf-life studies. While control samples at 4 and 22 °C were spoiled at the 15th and 3rd days, HHP treated samples were spoiled after 108th and 228th days, respectively.