Diethylenetriamine‐NO adduct (DETA) is an effective NO donor which has a long half‐life in aqueous solutions. This study was to determine whether dietary DETA supplementation to lactating sows can increase their production performance and the growth of their nursing piglets. Nine primiparous sows with average litter size of 11.5±0.3 were assigned to 2 treatments: CON (without DETA, n=5) and DT (with DETA 50 mg/d, n=4) between d 7 and 21 of lactation. Sows had free access to feed and drinking water. Body weights and backfat thickness of sows, as well as body weights of piglets were measured at d 0, 7, 14, and 21 of lactation. Body weight loss during 21‐d lactation were 17.0 and 11.0 kg for CON and DT, respectively (P>0.05). Backfat losses of sows were 0.8 and 0.5 mm for CON and DT, respectively (P>0.05). However, litter weight gain of DT (40.5 kg) was greater (P<0.05) than CON (36.5 kg) during d 7 to 21 of lactation. Feed intakes of sows were 7.2 and 7.5 kg/d for CON and DT, respectively (P>0.05). Dietary DETA supplementation to lactating sows improved the growth of nursing pigs possibly by enhancing nutrient outputs in milk due to increased blood flow across the mammary gland.