NOWADAYS, PROVIDING PRODUCTS WITH HIGH QUALITY AND SAFETY IS THE MOST CONCERN OF DAIRY INDUSTRIES WHEREAS STUDY OF VARIOUS CHARACTERISTICS OF THESE PRODUCTS COULD HELP TO FOOD INDUSTRIES AS WELL AS CONSUMER HEALTH. FOR THIS PURPOSE, IN THIS STUDY THE CHEMICAL PROPERTIES OF A TRADITIONAL CHEESE FROM RAW SHEEP MILK (POOSTI CHEESE) WERE EVALUATED DURING OVER A 90-DAYS RIPENING PERIOD. ACCORDING TO THE STANDARD PROCEDURE THE AMOUNT OF MOISTURE, ASH, ACIDITY, TOTAL NITROGEN (TN), SALT, PH, FAT, AND WATER -SOLUBLE NITROGEN (WSN) WERE DETERMINED FOLLOWED BY SAMPLING FROM POOSTI CHEESE DURING 1, 30, 60, AND 90 DAYS OF RIPENING. RESULTS OBTAINED SHOW THAT THE MOISTURE CONTENT OF POOSTI CHEESE DECREASED DURING ITS STORAGE AND ALSO THE AMOUNT OF TOTAL NITROGEN WERE INCREASED BY 1.5% AND THE FAT CONTENTS REDUCED TO SOMEWHAT DURING THE 90 DAYS OF RIPENING.