The work aims to investigate the effect of substrate materials and the addition of single-layer MXene (SL MXene) on the performance of flexible zinc-air batteries, as well as the battery performance in environments with different oxygen contents. Flexible zinc-air batteries were prepared on different substrate materials through screen printing. The effect of substrate materials on the discharge performance of flexible zinc-air batteries was studied. It was found that the discharge performance was the best for batteries printed on PE waterproof film, with the highest initial open-circuit voltage reaching 5.5V. Based on this, the effect of the mass fraction of SL MXene on the battery discharge performance was investigated. SL MXene of a single layer or few layers was obtained by etching and peeling Ti3AlC2 using a mixed solution of HCl and HF. When SL MXene was added to the air electrode ink, it was found that the discharge voltage of the flexible zinc-air battery remained stable when the SL MXene addition exceeded 2%, with no further changes. The discharge voltage also remained stable during bending. And after 200 bending cycles, the discharge voltage remained above 96%. When the oxygen content in the environment of the flexible zinc-air battery varies, its discharge voltage shows a positive correlation with the oxygen content, indicating its potential application in the field of oxygen smart packaging.