Growth performance, nutrient digestibility, faecal microbiota and blood profile response in growing-finishing pigs fed diet supplemented with poppy (Papaver somniferum L.) seed meal (PSM) were investigated. Sixty crossbred [(Landrace × Yorkshire) × Duroc] pigs weighing 25.2 ± 0.50 kg were used in an 84-day feeding trial and assigned to two groups: CON – basal diet; and PSM – basal diet + 2% PSM. Using a randomized complete block design, six replications were arranged according to sex and body weight (BW). The PSM diet significantly increased the average daily feed intake and BW (P = 0.052 and P = 0.053, respectively) of pigs during days 57–84 of trial in comparison to CON diet. In addition, the average daily gain was significantly greater during the last phase and overall experiment (P = 0.045 and P = 0.042, respectively) in pigs receiving PSM diet than in those receiving CON diet. Besides, PSM supplementation significantly reduced (P = 0.007) feed conversion ratio during the first 28 days in comparison to the CON diet. Also, the digestibility of dry matter in pigs fed the PSM diet was significantly greater at days 56 and 84 (P = 0.037 and P = 0.048, respectively), whereas nitrogen digestibility was unaffected during the whole experiment. However, no significant differences were observed in the faecal microbiota count and blood profile throughout the whole experiment. So, it can be concluded that the PSM can be used in the swine nutrition to improve growth performance and nutrient digestibility.