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The present-day trend in climate evolution toward aridization risk has also been observed in Romania, especially in its dryest regions, e.g. Dobrogea, where most of the crops have to be irrigated. This paper deals with the Penman-Monteith (PM) reference evapotranspiration (ETo) values, estimates of crop coefficients (K-c), optimum crop evapotranspiration (ETc), as well as irrigation water requirements (IWRs) of some fruit trees and grapes for a 38-year period within 17 locations within the Dobrogea region of Romania. K-c showed similar monthly values regardless of location, climate, soil and relief within the region; in addition to crop growth stage, PM-ET. was the main climatic parameter determining a difference in crop evapotranspiration. Estimated K-c values were compared to real K-c values obtained in field experiments under irrigation conditions. A strong, highly significant correlation between these two parameters for shorter periods was obtained, but crop evapotranspiration estimated by this method was slightly lower than real crop evapotranspiration previously reported for crops tested in this area. This could be attributed to inaccurate measurements of deep drainage and runoff in experiments formerly developed rather than to the deficiency of Allen's method. Dynamics of the ET, showed that July was characterized by maximum values. For the peak months, the IWRs of the fruit trees and grapes studied here were interpolated using the kriging method, resulting in relatively homogeneous crop IWRs areas. The paper confirms in Romania the method recently developed by Allen et al. (1998) in estimating K-c for any dry region or watershed. The findings of the present paper could also contribute to a better water management system in this semi-arid region with many high water consumers.