•Flexible and compressible conductive hybrid aerogels of PEDOT:PSS/PI were fabricated.•The hybrid displayed well-ordered “layer-strut” porous structure linked with fibrils.•The hybrid aerogel exhibited stable and linearly piezoresistive responses.•It retained good compressive sensitivity and durable stability in severe environments. The construction of flexible all-polymer-based conductive aerogels for piezoresistive pressure sensors is often hindered by a trade-off between robust mechanical properties and elastic-responsive conductivity. Here, a highly flexible and compressible conductive aerogel was fabricated by integrating poly(3,4-thylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) with polyimide (PI) through facile strategies of freeze-drying and thermal annealing. With a controlled ratio of the two components, the composite demonstrates a well-ordered and interconnected porous structure composed of “layer-strut” skeletons with linked fibrils. Benefiting from the unique structure and synergistic effects between the two polymers, the PEDOT:PSS/PI aerogel exhibits excellent compressibility, stable and linear piezoresistive responses at various compressive strains and good reproducibility over 200 cycles. Furthermore, the hybrid can retain good compression sensitivity and durable stability in severe environments, such as at high and low temperatures and under acidic conditions, demonstrating its great potential for a wide range of pressure sensor applications in harsh environments.