Based on the results of dissections of 126 pig carcasses, the proportions of pork belly and its parts, i.e. belly with bones, belly without bones and tip of belly, were determined. In addition, proportions of lean meat, bones, intermuscular and subcutaneous fat were determined in belly with bones as percentages of the weight before the dissection. Lean meat content of carcass was the most important factor for determining the pork belly composition. The correlation between lean meat content of carcass and lean meat percentage of belly with bones was 0.92 plus minus 0.035. Sex and slaughter weight had a greater impact on the composition of pork belly than the crossbred combination.