Technical Abstract: The purpose of this study was to compare effects of finishing environment on growth performance, pork quality, and lipid composition of pork. Environments compared were standard confinement (CON) and deep-bedded, semi-outdoor systems (Hoop). The deep-bedded method employed in the current study was the use of hoop structures. Hoops are large, tent-like shelters with cornstalks or straw for bedding. One hundred gilts ranging in weight from 59 to 71 kg were randomly assigned to treatments of Hoop (n = 50) and CON (n = 50) environments. Gilts were fed a two-phase dietary sequence, ad libitum for 45 days, afterwhich they were weighed and separated into six different weight groups. One gilt was randomly chosen to represent each weight group for performance, and carcass quality and composition measurements for both Hoop and CON treatments (n = 12). The experiment was replicated a total of five times. Pigs raised in the Hoop environment gained significantly less and required significantly more feed for growth than pigs raised in the CON environment. Carcasses from CON pigs were significantly fatter at the 10th rib, which lowered carcass percent fat free lean (% FFL). Carcasses from CON pigs had greater loin marbling scores compared to carcasses from Hoop pigs (P<0.05). Significant replication effects were noted on beginning weight, live weight, carcass weight, %FFL, backfat, lipid content, and adipose firmness. Carcasses from Hoop pigs had lower proportions of palmitic acid (P<0.05), and higher proportions of oleic and linoleic acid (P<0.05) in the inner layer of adipose tissue. Proportion of saturated fatty acid was lower, and proportion of polyunsaturated fatty acid was higher in inner layer of adipose tissue of Hoop pigs. Variations in fatty acid composition and lipid deposition may have been caused by environmental temperature, since decreases in environmental temperature accompanied compositional variation of the adipose, leading to higher proportion of monounsaturated fatty acid and lower proportion of saturated and polyunsaturated fatty acid in adipose tissue, regardless of treatment. Volatile profile analysis revealed that adipose tissue of Hoop pigs had significantly higher amounts of 3-butanal and heptanal compared to CON pigs, which may be related to the amount of oleic and linoleic acids composing the adipose tissue. These data indicate finishing pigs in Hoop structures allows for exposure to fluctuating temperatures, which may influence growth of pigs, as well as fatty acid composition and firmness of pork products.