Neoadjuvant immunotherapy can significantly improve the pathological complete response (pCR) and major pathological response (MPR) rates in resectable stage III non-small cell lung cancer (NSCLC), and extend the event-free survival (EFS). However, the current means for evaluating its efficacy are limited. This study aims to utilize the convenient and non-invasive 68Ga-grazytracer PET imaging to detect the aggregation of CD8+ T cells in target lesions after neoadjuvant immunotherapy for stage III NSCLC, and to assess its value in efficacy monitoring, providing valuable information for clinical treatment decisions.