The objective of this study was to evaluate the effects of dietary fat source and feeding duration on growth performance, carcass characteristics, and meat quality of finishing pigs. A total of 450 twenty-one-week-old finishing pigs with initial body weight of 113.7 ± 8 kg were housed in 90 pens and assigned to one of five dietary treatments in a 2×2+1 factorial design. Dietary treatments consisted of two fat sources (CWG: 4% inclusion of choice white grease and HOSO: 4% inclusion of high oleic soybean oil) each provided 2 or 4 weeks before marketing. The “+1” diet was a corn-based diet without fat inclusion (CON). Observations included pig growth performance (on d14 and d28 of feeding), carcass characteristics (12 pigs per treatment at marketing), fatty acid profile in the loins and bellies, and a consumer sensory evaluation. Data was analyzed using PROC MIXED in SAS considering dietary treatment as a main effect, feeding duration, and their interactions. Contrast tests were used to compare dietary treatments with control group. From d14 to 28 and overall experimental period (d0–28), pigs fed fat-supplemented diets had a greater (P< 0.05) average daily gain and gain to feed ratio than CON fed pigs. There was no significant difference (P>0.05) in growth performance when comparing fat sources or feeding periods. Pigs supplemented with either CWG or HOSO showed a tendency to have a greater (P< 0.1) belly weight and belly yield, and a lesser (P< 0.1) loin yield and loin muscle area when compared with CON pigs. Loins from the 2-week period of fat supplementation had darker (Coloration l, P< 0.05) meat coloration when compared with 4 weeks. The loin from pigs fed fat sources had greater (P< 0.05) concentration of oleic acid and eicosenoic acid when compared with CON. This improvement was mainly from HOSO. When CWG was compared with HOSO, pigs fed CWG had a higher (P< 0.05) concentration of palmitic acid and stearic acid while the HOSO pigs had a higher concentration of oleic acid and linolenic acid in the loin. In the belly, CON had higher (P< 0.05) concentration of palmitic acid and stearic acid while pigs fed fat sources had a higher concentration of oleic acid and eicosenoic acid. Bellies from HOSO had higher (P< 0.05) concentration of oleic acid and α-linolenic acid methyl ester while CWG had higher concentration of g-linolenic acid. As for the sensory evaluation, the palatability and acceptability of pork were not affected (P>0.05) by dietary treatments.