Oca tuber flours (Oxalis tuberosa) are obtained by freeze‐drying (OFFD) and heat‐drying (OFHD), and their physicochemical, thermal, rheological, antioxidant, and structural properties are studied. Amylose content is 16.03% and 18.81% in OFFD and OFHD, respectively. Total starch, resistant starch, and integrated dietary fiber are higher in OFFD. The thermal properties, final viscosity, and pasting temperature of the flours are not affected by the drying process. The use of heat to obtain Oca tuber flour causes a considerable reduction in total phenolic compounds and antioxidant activity. However, the same process leads to higher digestion rate and glycemic index. Microscopy analysis shows better dispersion of the starch granules (less agglomeration) in OFFD with irregular granule shapes. These results could facilitate the selection of the best method to obtain Oca tuber flour, which could help to expand the use of this tuber as an ingredient in industrial food products.