As consequence of the predicted climatic changes, analysis of the effects of drought stress on different plant species seems to be essential. In our study summer savory (Satureja hortensis L. ’Budakalászi’) was investigated in an open field experiment in the Experimental and Research Farm of the Szent István University in Soroksár. To identify the effect of water supply, irrigated (W) (additional 2 × 20 mm water per week) and non-irrigated control (C) treatments were applied on the plants with 50 × 30 cm growth distance. During the vegetation period water potential (pressure chamber) and the chlorophyll content (SPAD-502) were measured. Fresh and dry mass and leaf ratio were determined when plants were harvested at full flowering stage. The essential oil content was hydro-distilled with a Clevenger-type apparatus according to the Hungarian Pharmacopoeia (7th ed.). The essential oil composition was identified by GC-MS. The effect of the irrigation was obvious for the majority of the examined traits. The chlorophyll content decreased (W: 32.58 SPAD unit; C: 35.70 SPAD unit) while the water potential increased (W: -12.85 bar; C: -21.35 bar) significantly with water supply. The fresh mass (W: 104.00 g per plant) and dry mass (W: 14.09 g per plant) of the watered plants were higher compared to the untreated control (fresh: 60.55 g per plant; dry: 6.58 g per plant). The leaf ratio did not change significantly (W: 51.04%; C: 48.40%). The essential oil composition of savory seems to be independent from the water supply. The main components of the essential oil were carvacrol (50-51%), γ-terpinene (35-36%), and p-cymene (3-4%) in both oils. Irrigation decreased the accumulation level of the essential oil (W:  4.289 ml 100 g-1 DM; C: 4.859 ml 100 g-1 DM). However,  due to higher biomass,  the essential oil yield of well-watered plants was higher. Based on this information we may declare that during the cultivation of savory, additional irrigation seems to be necessary.