The research was carried out on 24 pigs kept in the outdoor (extensive) and 24 pigs kept in the semi-outdoor (semi-intensive) keeping system. In each group there were 12 barrows and 12 gilts. Pigs in both systems were fattened up to 100kg (n=12) and 130kg (n=12) body weight. The pigs from the indoor system were grazing on pastures and stubble-fields, with minimum addition of corn (150 g/day) during winter, when there is no green forage, whereas the pigs kept in the semi-outdoor system were fed ad libitum a combination of feed mixture and green alfalfa. The feed mixture used in the first fattening phase (30 - 60 kg body weight) contained 14% crude protein and 13.37MJ ME/kg, and in the second phase (60-130kg body weight) it contained 12% crude protein and 13.34MJ ME/kg. Dissection of cooled (+4°C) right half-carcasses was carried out according to modified Weniger et al. method (1963). Meat quality (Muscullus longissimus dorsi) was examined in terms of the pH value, water binding capacity and colour. The pH1 value of meat was determined 45 minutes post mortem and pH2 value 24 hours post mortem, by means of the pH-meter Mettler Toledo. Water binding capacity was determined according to Grau and Hamm (1952), and colour (CIE – L, a and b values) by means of a Minolta CR-410 chroma meter. Statistical processing of research results, variance analysis, was carried out by means of Stat. Soft. Inc. 2012. Meatiness of half-carcasses in both production systems was higher in pigs of lower body weight (100kg), compared to pigs of higher body weight (130kg). However, these differences were significant (p<0.05) only in the pigs kept in the semi-outdoor system. Pigs from the indoor system had meatier carcasses in relation to pigs from the semi-outdoor system both at lower (100 kg) and higher (130 kg) body weights, but it was not statistically significant (p>0.05) (49.23% and 44.99% : 46.56% and 42.82%). A significant influence of the keeping system and body weight was detected for some indicators of meat quality. Meat of pigs of lower body weight from the outdoor system had a significantly higher (p<0.01) level of crude protein than meat of pigs kept in the semi-outdoor system at the same body weight. No significant differences were detected in terms of crude fat content, regardless of the production system and body weight of pigs.