The limited triple phase boundaries (TPBs) in solid state cathodes (SSCs) and high resistance imposed by solid electrolytes (SEs) make the achievement of high-performance all-solid-state lithium-oxygen (ASS Li-O2) batteries full of thorns. Herein, a porosityadjustable plastic crystal electrolyte (PCE) has been successfully fabricated by employing a thermally induced phase separation (TIPS) technique to overcome the above tricky issues. The meticulous designed SSC through in-situ introducing porous PCE on the surface of active material, facilitates the simultaneous transfer of Li+/e- , as well as ensures fast flow of O2, forming continuous and abundant TPBs. The high Li+ conductivity, softness and adhesion of the dense PCE significantly reduce the battery resistance to 115 Ω. As a result, the ASS Li-O2 battery based on this porosity-adjustable PCE exhibits superior performances with high specific capacity (5963 mAh/g), good rate capability and stable cycling life up to 130 cycles at 32 ºC. This novel design and exciting results could open a new avenue for ASS Li-O2 batteries.