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We researched the influence of soil cultivation and fertilization on changes of nitrate, ammonium and inorganic nitrogen content in soil during the monitored vegetation periods (2004/2005 – 2005/2006). This experiment was realized on experimental bases of Slovak University of Agriculture in Nitra – Dolná Malanta on the winter/summer wheat (Triticum aestivum), variety Bonita, with red clover as its before-crop. In the field trial we used two types of tillage, B1 – conventional tillage up to the depth of 0,25 m and B2 – disc ploughing up to 0,15 m, with three variants of fertilization, 0 – unfertilized control, PH – fertilization according to its content in soil and PZ – fertilization according to its content in soil + plough down of post harvest residues. Samples of the soil were taken from the two soil depth (0,0- 0,3 m and 0,3-0,6 m) and in each vegetation period there were 8 takings of soil samples in four repetitions. During monitored vegetation period this dynamics was changeable. The content of nitrate nitrogen in the soil in autumn was about 40 % higher than content of ammonium nitrate. This tendency changed in spring, when the average content of ammonium nitrogen was higher than the content of nitrate nitrogen on average about 60 %. The cultivation had significant influence on dynamics of inorganic nitrogen. The average content of inorganic nitrogen in conventional tillage up to the depth of 0,25 m was 8,43 mg.kg-1 and in disc ploughing it was 7,60 mg.kg-1. The influence of fertilization on changes of inorganic nitrogen was significantly important. Monitored ways of fertilization within the content of nitrates in the soil had the following averages: in unfertilized soil 7,48 mg.kg-1, in fertilized soil NPK 8,20 mg.kg-1 and in the soil fertilized with plough down of post harvest residues 8,37 mg.kg-1. In the first and second variety of soil cultivation we found out a low increase of average concentration of nitrates in the fertilized soil in comparison with unfertilized one. High significant influence on dynamics of nitrate nitrogen in the soil had date of sample takings and also depth. In the first depth (0,0-0,3 m) the level of nitrate nitrogen was 9,18 mg.kg-1 and in the second depth (0,3-0,6 m) it was 6,85 mg.kg-1., V práci bola sledovaná dynamika obsahu anorganických foriem dusíka v pôde pod pšenicou letnou f. ozimnou, v priebehu dvoch po sebe nasledujúcich vegetačných období (2004/2005 a 2005/2006), na výskumno-experimentálnej báze Slovenskej poľnohospodárskej univerzity v Nitre – Dolná Malanta. V pokuse boli použité dva spôsoby obrábania pôdy ( B1 - stredne hlboká orba do 0,25 m, B2 – tanierovanie), tri varianty hnojenia (0 – bez hnojenia, kontrolný variant, PH – priemyselné hnojivá a PH + ZV – priemyselné hnojivá so zapracovaním pozberových zvyškov predplodiny). Vzorky pôdy boli odoberané z dvoch hĺbok pôdy (0,0-0,3 m a 0,3-0,6 m), pričom v každom vegetačnom období bolo realizovaných 8 odberov pôdnych vzoriek v štyroch opakovaniach. Počas nášho sledovaného vegetačného obdobia bola táto dynamika premenlivá. Dusičnanová forma dusíka v pôde v jesenných mesiacoch tvorila vyšší obsah v priemere o 40 % viac ako amónna forma. Tento trend sa však zmenil v jarných a letných mesiacoch, kedy priemerný obsah amónneho dusíka bol vyšší ako dusičnanový dusík v priemere o 60%. Obrábanie malo na dynamiku Nan vysoko preukazný vplyv. Pri obrábaní pôdy stredne hlbokou orbou do 0,25 m (variant B1) bola priemerná koncentrácia anorganického dusíka 8,43 mg.kg-1 a pri tanierovaní (variant B2) 7,60 mg.kg-1. Vplyv hnojenia na zmeny koncentrácie Nan bol štatisticky vysoko preukazný. Sledované spôsoby hnojenia v rámci obsahu dusičnanov v pôde zaznamenali nasledovné priemery: v nehnojenej pôde 7,48 mg.kg-1 , hnojenie NPK 8,20 mg.kg-1 a v pôde hnojenej so zaoraním pozberových zvyškov 8,37 mg.kg-1. V prvom aj v druhom variante obrábania pôdy sme zaznamenali mierny nárast priemerných koncentrácií Nan v hnojenej pôde proti nehnojenej kontrole. Vysoko preukazný vplyv na dynamiku dusičnanového dusíka v pôde mali aj termíny odberov pôdnych vzoriek ako aj hĺbka.