The aim of the present study was to evaluate the effect of plough and conservation tillage treatment as well as various catch crops on the chemical composition of the grain of spring wheat grown in monoculture. The study was carried out in 2006–2008, using an experiment established in 2005. The experimental field was located on medium and heavy mixed rendzina soil. The design of a static two–factor experiment, set up using the split-plot method in four replications, included the plough tillage system (A) and two conservation tillage methods – with autumn (B) or spring (C) disking of catch crops. The other factor comprised four methods for regeneration of the spring wheat monoculture stand using the following catch crops: undersown red clover (b) and Westerwolds ryegrass (e); lacy phacelia (c) and white mustard stubble crops (d); and the control treatment without catch crops (a). The concentrations of potassium, manganese and sulphur in the spring wheat grain harvested from the ploughed plots were higher than in the conservation tillage treatment. In the plough tillage treatments, grain Mg content was higher than in the conservation tillage variant with spring disking of the catch crops. Conservation tillage had an effect on the increase in phosphorus and copper content in spring wheat grain compared to plough tillage. Zn and Fe content in the grain from the conservation tillage treatments with autumn disking of the catch crops was lower than in that from the plough and conservation tillage treatments with spring incorporation of the catch crops. Iron content in the grain obtained from the treatments with red clover and lacy phacelia was the highest. At the same time, phosphorus content in spring wheat grain was the highest in the control treatments and in the treatment with Westerwolds ryegrass and white mustard. In the plots where a lacy phacelia stubble crop had been sown, zinc and copper content in grain was determined to be the highest. In turn, the highest manganese content was found in the grain from the control treatments, whereas total sulphur content was the highest in the control plots and in the plots with the stubble crops.