The “Branca” breed is a dual-purpose Portuguese autochthonous chicken breed, produced in extensive systems and in small flocks, especially in the Entre Douro and Minho regions. A total of 40 birds (n = 20/sex) were slaughtered between 38 and 42 weeks (males) and 110 and 120 weeks (females), and carcass and meat quality parameters were evaluated. The results showed significantly higher weights and differences for males between sexes and pieces (p ≤ 0.05) in the meat physicochemical composition. Water holding capacity (WRC), moisture and ash contents were influenced by sex. They were higher in males in the breast and drumstick and lightness (L*) and lipid content were higher in females (p ≤ 0.05). The breast meat presented greater lightness, moisture, ash and protein contents, while the drumstick showed a higher pH value, redness (a*) and lipid content, in both sexes (p ≤ 0.05). Regarding the nutritional properties, “Branca” meat revealed a good proportion of minerals and the female meat showed, in both pieces (p ≤ 0.05), significantly lower values for total saturated fatty acids (SFAs) and higher values for monounsaturated fatty acids (MUFAs). Breast meat was richer in n-3-PUFAs (C22:5n-3 and C22:6n-3) in both sexes (p ≤ 0.05). Considering the results obtained, it can be concluded that “Branca” breed meat is a healthy food characterized by a good general nutritional profile.