SPECT/CT imaging of lung cancers with 99mTc‐HYNIC‐αLAG‐3 and 99mTc‐HYNIC‐αPD‐L1 probes represents an effective method for noninvasively visualizing human LAG‐3 and PD‐L1, as well as immunotherapy resistance monitoring. Here, LAG3 is linked to lung carcinoma.