In this work, we present an oxygen-releasing insole to treat diabetic foot ulcers. The insole consists of two layers of polydimethylsiloxane: the top layer has selective laser-machined areas (to tune oxygen permeability) targeting the ulcerated foot region, while the bottom layer provides structural support and incorporates a chamber for oxygen storage. When loaded with a pressure of 150 kPa (average value for standing/walking), the insole is able to release oxygen at a rate of 1.8 mmHg/min/cm2. At lower sitting pressures, the delivery rate persists at 0.092 mmHg/min/cm2, raising the oxygen level to an optimal healing value (50 mmHg) for a 2 × 2 cm2 wound within 150 min.