The emergence of wearable technology can significantly benefit from electronic displays fabricated using intrinsically stretchable (is‐) materials. Typically, an improvement in the stretchability of conventional light‐emitting polymers is accompanied by a decrease in charge transportability, thus resulting in a significant decrease in device efficiency. In this study, a self‐assembled 3D penetrating nanonetwork is developed to achieve increased stretchability and mobility simultaneously, based on high‐molecular‐weight phenylenevinylene (L‐SY‐PPV) and polyacrylonitrile (PAN). The mobility of L‐SY‐PPV/PAN increases by 5–6 times and the stretchability increases from 20% (pristine L‐SY‐PPV film) to 100%. A high current efficiency (CE) of 8.13 cd A−1 is observed in polymer light‐emitting diodes (PLEDs) fabricated using 40% stretched L‐SY‐PPV/PAN. Furthermore, using a polyethyleneimine ethoxylated (PEIE), an 1,10‐phenanthroline monohydrate (pBphen), and a reduced Triton X‐100 (TR) chelated Zn‐based is‐ electron‐injection layer of Zn‐PEIE‐pBphen‐TR, an is‐PLED is realized with a turn‐on voltage of 6.5 V and a high CE of 2.35 cd A−1. These results demonstrate the effectiveness of using the self‐assembled 3D penetrating nanonetwork for the fabrication of is‐PLEDs.