Young shoots of wheat in the early stage of growth, and before the plant enters the stem extension phase, are called wheatgrass. It is rich in minerals, vitamins, chlorophyll, enzymes, bioflavonoids and due to the quality of its nutritional composition it is used in human and animal nutrition as a natural supplement and thus is classified as a functional food. In the fresh state after cutting or after storage, fresh leaves or their juice are consumed, and preparations in the form of powders or tablets can be found on the market. The aim of the study was to examine the effect of storage duration (0, 7, 14 and 21 days) and storage temperature (4 °C, -18 °C, -80 °C) of wheat grass juice or leaf tissue samples on the total ascorbic acid content, as the most important antioxidant and nutritional quality indicator. On the day of cutting, the highest content of vitamin C in the leaves and juice of wheat grass was determined. On average for both variants of tissue storage, already after the first day there was a significant decrease in the concentration of vitamin C compared to the control analyzed on the day of cutting. Storage of wheat grass leaves and sap at -80 ºC resulted in significantly lower oscillations of the downward trend in vitamin C content, compared to other storage temperatures. A significant decrease in the content of vitamin C was found in the juice, in contrast to the tissue of wheatgrass leaves. The results show that from the nutritional aspect and the content of vitamin C, it is best to consume wheat grass fresh. Also, if necessary, it is much better to store leaf tissue for a longer period and prepare fresh juice from it on the day of consumption, than to store juice prepared on the day of cutting.