It is widely acknowledged that gasdermin family proteins, which are known as the executors of pyroptosis, undergo protease-mediated cleavage prior to inducing pyroptosis. Here, we unexpectedly discovered a non-canonical form of pyroptosis mediated by full-length GSDME (FL-GSDME) without any proteolytic cleavage. Upon intense ultraviolet (UV) irradiation-triggered DNA damage, hyperactivation of nuclear PARP1 led to extensive formation of poly(ADP-ribose) (PAR) polymers and then release to the cytoplasm.These PAR polymers activate PARP5 to catalyze GSDME PARylation, resulted in a conformational change in GSDME that relieved autoinhibition imposed by its C terminus on the N terminus. On the other hand, intense UV irradiation boosted mitochondrial fission-dependent generation of mitochondrial reactive oxygen species (mito-ROS), further promoting cytochrome c-catalyzed peroxidation of cardiolipin. This lipid-ROS signal was then sensed by PARylated-GSDME and then induced oxidative oligomerization of GSDME, which facilitated FL-GSDME plasma membrane targeting for perforation, eventually inducing pyroptosis. Reagents that concurrently stimulate PARPs activity and lipid-ROS also induced sequential modifications i.e., PARylation and oxidation of FL-GSDME and synergistically promoted pyroptotic cell death. Overall, our findings elucidate a novel mechanism underlying cleavage-independent function of GSDME in executing cell demise, further enriching the paradigms and cognition of FL-GSDME-mediated non-canonical pyroptosis.