Garlic and dandelion contain bioactive constituents with multifarious properties including antibacterial, anti-inflammatory, antioxidant, immunomodulatory, and prebiotic activity, which exert a positive effect on the health and productivity of animals. Therefore, the study evaluated the effects of garlic or dandelion and their combination in diets on the performance, carcass traits, and fatty acid composition in some tissues and organs of fatteners. Four dietary treatments were designed: C - control fed conventional diet, G - supplemented with 5 g/kg diet of lyophilised garlic, D - supplemented with 50 g/kg diet of dandelion root powder and GD – receiving both phytobiotics (applied in the same amounts as in the G and D treatments). The experiment was performed on 80 crossbred pigs (25–115 kg of body weight) assigned into one of 4 dietary treatments with 5 replicate pens per treatment and 4 pigs per pen (2 gilts and 2 barrows). The 95-day long experiment was divided into three phases over the growing-finishing period, with a specific diet for each phase. Improved performance, reduced content of fat and cholesterol levels in backfat, longissimus lumborum (LL) muscle, and liver were noted in the G and GD treatments, compared to the control treatment (P < 0.05). The GD treatment increased the loin eye area and lean meat yield (P < 0.05). The content of polyunsaturated fatty acids was increased in LL and backfat upon the addition of phytobiotics (P < 0.05). In the GD treatment, the fat of LL and liver exhibited a better n-6/n-3 ratio than the control (P < 0.05). The combined addition of garlic at a dose of 5 g/kg diet and dandelion at 50 g/kg was the most efficient in increasing the growth performance, carcass quality traits, and some indices of nutritional fat quality.