Mineral fertilization is one of the most important components of proper cultivation technology of spring wheat. It actually determines the quantity and quality of grain yield. In 2011-2013 a strict field experiment was carried out which aimed to determine the response of chosen spring wheat cultivars to two NPK fertilization levels. In the research hypothesis it was assumed that varied rates of NPK fertilization will modify the canopy structure, the state of plant nutrition and the quantity and quality of spring wheat grain yield. Two fertilization levels were used: 80 N; 43.6 P and 83 K kg·ha^-1 (level I) and 120 N; 65.4 P and 124.5 K kg·ha^-1 (level II). The tested cultivars were: Hewilla, Monsun, Nawra, Ostka Smolicka, Waluta, Zadra, Żura. The higher rate of mineral fertilization in comparison with the lower one resulted in a significant increase in SPAD and LAI indices values, whereas it did not modify MTA index. The number of ears per 1 m² was higher on treatment with the higher fertilization level as compared with the lower. The obtained difference was significant and on average it amounted to 26 no.· m². The number of grains per ear and TGW were not modified by the fertilization factor. Spring wheat gave the highest yields in 2012 and the lowest in 2013. After the use of the higher fertilization level, the mean grain yield amounted to 5.83 Mg·ha^-1 and was significantly higher than on the treatment with the lower fertilization level (4.89 Mg·ha^-1). Plants of the cultivar Ostka Smolicka were characterized by a significantly higher LAI index in relations to the cultivar Monsun, whereas MTA index was significantly higher in plants of the cultivar Waluta in comparison with the cultivar Żura. The highest value of SPAD index was recorded in plants of the cultivars Hewilla and Ostka Smolicka, and significantly lower in the cultivar Żura. Moreover, a significant difference was indicated in SPAD between the cultivars Nawra and Ostka Smolicka. Plants of the cultivar Waluta lodged significantly heavier than those of the cultivar Nawra. More plump grains were formed by Nawra as compared with Zadra. Ostka Smolnicka was characterized by the highest yield, and Monsun, Nawra and Waluta by significantly lower yields. Also it was proved that Hewilla has a significantly higher grain yield than Nawra. Experimental factors did not have a significant effect on total protein content in grain.

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