Commercial oat flour and certified gluten-free wholemeal oat flour were used to make muffins according to a recipe for gluten-free bakery wares. The use of oat flours instead of a mix of rice and maize flours with maize starch caused the content of the following components in the muffins produced to significantly (p ≤ 0.05) increase: total proteins (9.11 ÷ 10.29 % d.m.), fat (15.06 ÷ 15.41 % d.m.), and minerals in the form of total ash (1.75 ÷ 2.03 % d.m.). Particularly large changes were reported in the case of the fibre fraction; its content increased almost three times upon the application of wholemeal oat flour. Oat flours, especially gluten-free flour, were, in the muffins, a source of substantial amounts of β-D-glucans (2.89 % d.m.), an important component of the soluble fraction of dietary fibre. The differences in the volume of muffins produced were statistically significant (p ≤ 0.05) but minor, and they did not significantly impact the texture parameters. As for the oat products, the rate of changes in those parameters was lower over the entire period of storage. As early as on the day of baking, the muffins made from oat flour were characterized by a lower hardness (34.8 ÷ 36.9 N) compared to the products from flour mix (51.0 N); those differences increased on the 3 subsequent days of storing (respectively, 40.8 ÷ 44.1 N, 88.8 N). Irrespective of the type of oat flour used, the products made from it were characterized by a good appearance and an attractive taste and flavour. Of the analyzed oat flours, the certified gluten-free flour was the only one to provide an appropriately low content of gluten proteins (12.8 mg gluten/kg); therefore, the products produced could be considered to be gluten-free. Thus, the muffins from commercial oat flour (166 mg gluten/kg) can be consumed only by healthy people who choose oat products owing to their pro-health values and taste.