Display omitted •Surface micro-dissolution method was proposed to introduce polyaniline to polyester textiles.•The preparation was easy to perform, which was carried out at 70 ℃ for 15 min.•Resulting textiles show good electrical and electrothermal performances.•Resulting textiles were assembled into flexible electrodes and showed high electric capacity. Incorporation of PANI with polyethylene terephthalate (PET) fibers has creates many flexible conductive, electrothermal and energy-storage textiles. The most common method of depositing PANI to PET fibers is in-situ polymerization. However, it usually needs long reaction time and strict conditions, which is unbeneficial to large-scale commercialized process. Herein, a facile and high-efficiency surface micro-dissolution method was proposed to prepare PANI-coated PET fabrics, which is performed at moderate temperature (70 °C) and only needs 15 min of treatment time. Already-made PANI powders were directly used as raw materials, and the phenol/N-methyl pyrrolidone (phenol/NMP) solution worked as the surface micro-dissolution agent. The resulting fabrics show electroconductive (620 Ω/□), electrothermal (from 22.3–30.3 ℃ within 1 min) and energy storage (438.51 m F cm−2) performances. The preparation is easy to perform and of very high efficiency, making it suitable for industrial production of PANI-coated PET fabrics.