This paper is aimed at examining the impact of change of sowing structure on the employment of labour force and on the economic effects of business operations of farms directed at final production of fattened beef cattle in the conditions of unchanged estate size. Thereby, appropriate models of family farms directed at fattening of beef cattle are formed and they serve for considering organisational and economic effects of changes in sowing structure. Applying partial budget analysis, it was examined whether the decision on changing the sowing structure was economically justified and under what conditions by using an additional procedure of analysis. Applying this approach, it was determined to what extent that decision contributed to economic effects of the family farm business. A detailed analysis of natural, organisational and economic conditions in which these farms operate was previously carried out so as to successfully accomplish the given aim, and then the analysis of all available resources was conducted as well as the analysis of production results. The data for this survey were collected during the year of 2012 by interviewing holders of the chosen family farms directed at the final production of fattened beef cattle. For the purpose of considering the effects of change in sowing structure, the results of previous research related to employment of labour force in crop and livestock production were used. In this regard, the results of the conducted research show that more rational way of organization (change in sowing structure) provides an opportunity for family farms directed at the final production of fattened beef cattle to use available resources (especially labour force) in a better way, and thus to improve economic effects of the family farm business.