A representative set of pig carcasses (n=390) was analysed to determine the effects of different factors on the composition of belly. Detailed anatomical dissections of bellies were performed and the results were analysed with the aim to determine the effects of sex, carcass weight and meat yield. Regression equations for belly composition prediction were calculated. Carcass parameters measured during carcass classification were used as dependent variables in these equations, and predicted tissue proportions in the belly with bones were the results. Furthermore, for the purpose of practical use in slaughterhouses, equations were also calculated to predict absolute and relative tissue proportion in the belly with bones as defined by the meat industry.