The relationship between meat quality traits and carcass lean content was checked in 63 pigs graded according to EUROP classification. In each of the E, U, R, O classes there were 12, 13, 27 and 11 pigs, respectively. They were slaughtered at 105 kilograms liveweight. Carcass lean content (CLC) was predicted by UFOM-100 device. The CLC in each of the E, U, R, O classes attained 58.5 +/- 3.2, 52.4 +/- 1.4, 47.9 +/- 1.3 and 42.2 +/- 1.2%, respectively. Meat quality generally tended to increase with the decrease of CLC. The pH(1) has increased from 5.97 in E to 6.49 in O class (P < 0.01). The LF1 values were highest in E class 7.67 mS and gradually decreased to 3.36 mS in O class (P < 0.01). Drip loss was highest in E and lowest in O class (P < 0.01). The inverse was the case in water holding capacity of meat (P < 0.01). It is concluded that some meat quality deterioration may be expected in heavy muscled pigs.