Carrot is an important source of sugars.The objective of this study was to investigate the effects of water supply (precipitation + irrigation) on the concentration and ratio of fructose, glucose, and sucrose in carrot.Irrigation did not decrease the dry matter content and the summed concentration of the three measured sugars.Glucose accumulation was not inf uenced either by irrigation or by year.Low amount of precipitation during the early growing period was detrimental for fructose accumulation.Irrigation enhanced sucrose concentration, presumably by ensuring better photosynthetic activity.However, dry and hot weather during the irrigation cut-off period in 2011 also resulted in increased sucrose accumulation, presumably as a stress effect.It was found that irrigation did not inf uence the ratio of the three investigated saccharides at all, and even the growing year had just a slight effect on that.