In the cultivation of carrots on alkaline soil, the problem is low level of plant accessible phosphorous taking into consideration that it represents an essential element for the growth, development, yield and quality of carrots. The application of NPK fertilizers meets the requirements of crops for nutrients. However, there is no known reaction of different carrot varieties to phosphorus added through the same amount of NPK fertilizers. The aim of the study is to determine the reaction of varieties of carrots and the change in the accessibility and use efficiency of phosphorus when applying different amounts of NPK fertilizers in alkaline soil. A field fertilizer trial was set using the method of a randomized fertilization block (0, 55, 82.5, 110 kg P2O5 / ha) and the varieties of carrots ‘Namibia’ and ‘Soprano’ in three repetitions along with irrigation. The fertilization was done by using Yara Mila Complex NPK 12-11-18 + Yara Liva Nitrabor. The variety ‘Soprano’ has taken up a higher rate of P compared to variety ‘Namibia’ regardless of the fertilization. On the other hand, there was a higher utilisation efficiency of phosphorus determined for the variety ‘Namibia’ in regard to variety ‘Soprano’.