Programmed　cell　death　ligand　1　(PD-L1)/programmed　cell　death　protein　1　(PD-1)　checkpoint　inhibitor-based　immunotherapy　has　provided　a　unique　and　potent　weapon　against　cancer　in　clinical　practice.　The　likelihood　of　achieving　beneficial　effects　from　PD-L1/PD-1　immune　checkpoint　blockade　(ICB)　therapy　is　clinically　assessed　by　detecting　PD-L1　expression　through　invasive　tissue　biopsies.　However,　PD-L1　expression　is　susceptible　to　tumor　heterogeneity　and　dynamic　response　to　ICB　therapy.　Moreover,　currently,　anti-PD-L1　immunotherapy　still　faces　challenges　of　the　low　targeting　efficiency　of　antibody　drugs　and　the　risk　of　immune-associated　adverse　events.　To　overcome　these　issues,　advanced　nanotechnology　has　been　developed　for　the　purpose　of　quantitative,　non-invasive,　and　dynamic　analyses　of　PD-L1,　and　to　enhance　the　efficiency　of　ICB　therapy.　In　this　review,　we　first　introduce　the　nanoprobe-assisted　in　vitro/in　vivo　modalities　for　the　selective　and　sensitive　analysis　of　PD-L1　during　the　diagnostic　and　therapeutic　process.　On　the　other　hand,　the　feasibility　of　fabricating　diverse　functional　nanocarriers　as　smart　delivery　systems　for　precisely　targeted　delivery　of　PD-L1　immune　checkpoint　inhibitors　and　combined　therapies　is　highlighted.　Finally,　the　current　challenges　are　discussed　and　future　perspectives　for　PD-L1-targeted　cancer　theranostics　in　preclinical　research　and　clinical　settings　are　proposed.　Advanced　nanotechnology　developed　for　PD-L1　detection　and　PD-L1/PD-1　immune　checkpoint-relevant　combined　cancer　therapies　is　reviewed.