Options for odor control from tunnel-ventilated swine barns are limited. Automated scrapers have proven successful for reducing odor at free-stall dairies and for reducing hydrogen sulfide at a research-scale swine facility, but their effectiveness for reducing odor in commercial tunnel-ventilated swine barns has never been evaluated. A research project was conducted to compare odor concentrations in exhaust of traditional flush barns and barns equipped with automated scrapers. The study was conducted at commercial tunnel-ventilated swine barns owned by Premium Standard Farms LLC in northwest Missouri. Odor samples were collected from the barn exhaust in Tedlar bags and analyzed by trained human panelists using triangular forced-choice olfactometry. Total reduced sulfur (TRS) concentrations were measured with a portable Jerome meter, and volatile organic compounds (VOCs) were sampled in sorbent tubes and analyzed by gas chromatography/mass spectrometry. Mean odor concentrations (dilutions to threshold, DT) were 75.6% lower in exhaust from scraper barns (DT = 941) than flush barns (DT = 3860) (p < 0.001). Mean recognition thresholds (RT) were 76.4% lower in exhaust from scraper barns (RT = 494) than flush barns (RT = 2095) (p < 0.001). TRS concentrations averaged 1.59 and 0.16 ppm in flush and scraper barns, respectively, for an 89.9% difference (p = 0.029). Hedonic tone and intensity were statistically similar for flush and scraper barns. Odor was positively correlated with TRS in flush barns, while in scraper barns odor was positively correlated with butyric acid, 4-ethylphenol, indole, and skatole. Odor concentrations were significantly greater during flush than between flush events (p = 0.002), but there was no difference in mean odor concentrations during scrape and between scrape events (p = 0.20). These results show that scraper barns are a practical alternative for the control of odor emitted from tunnel-ventilated swine barns.