Duck grease (DG), a by-product of duck industry, is abundant and inexpensive as a potential energy feed source because more than 60% of global ducks are produced in China. However, the nutritive value of DG in swine diet has not been assessed. In our previous study, the apparent digestible energy and metabolizable energy have been evaluated. The present study addressed the effects of DG compared with soybean oil (SO) on growth performance, carcass characteristics and meat quality in a 82 d feeding program. A total of 72 growing barrows (31.62 ± 2.31 kg initial body weight) were randomly assigned into 2 dietary treatment groups in 6 replicates/pens utilizing a completely randomized design. The pigs were fed a corn-soybean meal based diet containing same amount (2% in growing diet, 1% in finishing diet) of SO or DG. One pig at average body weight in each pen was electrically stunned and slaughtered at the end of the feeding experiment, and carcass characteristics and pork quality were measured. Unpaired t-test was applied to evaluate the comparisons between 2 groups. Growth performance and carcass characteristics were not different (P > 0.05). Pigs fed DG improved the apparent total-tract digestibility of dry matter (DM; 82.19 vs. 86.46%, P < 0.05) and gross energy (GE; 81.22 vs. 84.17%, P < 0.05). Visual color, ultimate pH, marbling score, and driploss were not different between DG and SO treatment. The intramuscular fat (IMF) content (2.77 vs. 3.67%, P < 0.05) and muscle fiber density (1112.82 vs. 1389.97 fiber number /mm², P < 0.05) in longissimus dorsi (LM) were increased, while slice shear force was decreased in DG fed pigs (5.94 vs. 4.54 kg, P < 0.05). In conclusion, dietary DG improved pork quality without negatively influencing growth performance and carcass characteristics in growing-finishing pigs.