Moldova is one of Europe's largest producers and exporters of walnuts and kernels walnuts, reaching about 10 000 tonnes per year [1]. They are mainly used for the production of biscuits, bread, cakes, ice cream, sauces, as well as for the production of cold pressed oil. Walnut oil is prized as specialty oil because of its characteristic flavor and aroma and its potential health benefits [2]. Presently, a great attention is paid to the new technologies that permit to obtain natural biologically active compounds. One of these is the supercritical extraction with carbon dioxide. The advantages of this method of extraction with CO2 as solvent: it is non-toxic, volatile, easy to recover, with high diffusion rates, good mass transfer and low cost. A rich source of biologically active compounds is walnut kernel having medicinal properties that are known for centuries. Walnut kernels contain functional food ingredients: proteins, polyunsaturated fatty acids (PUFA), dietary fiber, minerals and vitamins. In this context, we have been studied the CO2-extraction technology of walnut kernels. It was studied the parameters of extraction process (particle size, pressure, temperature and time). It was established the fatty acids content of the walnut CO2-extract and its stability during storage for seven months. The CO2-extract of walnuts is a source of essential fatty acids (EFAs), phytosterols and vitamin E. Among the fatty acids the predominant are: linoleic (63.94%), linolenic (9.32%) and oleic acid (17.08%), but in the smaller amounts are the palmitic (7.52%), stearic (2.14%) palmitoleic, behenic, gadoleic and myristic acids. The bibliographic sources [3] show that the CO2-extracts are foods with better properties and characteristics than the oils obtained by other solvents or cold pressed oils. In order to verify these claims, it was analyzed the following oils: walnut kernel oil obtained by cold pressing, CO2-extract of walnut kernel and the walnut oil extracted by hexane. In these oils were determined the quality indices, shown in figure 1 and 2, which were kept for seven months, under the same conditions of temperature (5-7°C) and humidity (60-75%) in the refrigerator, in order to establish the validity term. Fig. 1. Evolution of the peroxide value Fig. 2. Evolution of the acid value After seven months of storage of three simples of walnut oil obtained by different methods, the acidity value rests unchanged, but the peroxide value increased a lot for hexane oil. During the storage the CO2-extract of walnut kernel was stable at oxidative modifications. According to the evolution of peroxide (figure 1 and 2) it was established that the CO2-extract of walnut kernel could be kept for 5 months, the cold pressed oil - 2 months and the oil extracted with hexane - 1 month. The CO2-extract of walnut kernel contains in ideal proportion ω-3/ω-6 fatty acids – the ratio linolenic/ linoleic acids being 1/6.86, so it is recommended for healthy food.