The　efficacy　of　programmed　cell　death-ligand　1　(PD-L1)-based　immune　checkpoint　blockade　therapy　(ICBT)　depends　on　the　tumor　PD-L1　expression　level.　Accurate　evaluation　of　tumor　PD-L1　is　essential　to　identify　patients　who　will　benefit　most　effectively　and　to　develop　appropriate　treatment　strategies.　However,　high-sensitivity　evaluation　of　microtumor　PD-L1　expression　remains　challenging　in　current　ICBT　landscape.　Here,　we　develop　a　PD-L1-targeted　near-infrared　(NIR)　persistent　luminescence　(PersL)　nanoprobe,　termed　mZ-PD-L1,　and　establish　a　high-sensitivity　PD-L1　imaging　technique　based　on　NIR　PersL.　This　method　allows　high-sensitivity　and　precise　imaging　of　PD-L1　in　microtumors　and　micrometastases　in　vivo.　mZ-PD-L1　exhibits　biowindow-activated　reproducible　NIR　PersL　properties,　along　with　exceptional　PD-L1　targeting　capability.　By　conducting　in　vivo　NIR　PersL　imaging,　mZ-PD-L1　facilitates　high-sensitivity　visualization　of　tumor　PD-L1　expression.　Using　mZ-PD-L1,　we　achieve　high-sensitivity　and　precise　imaging　of　PD-L1　in　microtumors　(≤1　mm)　and　lymph　node　micrometastases,　with　imaging　signal-to-background　ratios　as　high　as　27　and　37,　respectively.　This　study　provides　a　strategy　to　precisely　and　comprehensively　evaluate　PD-L1　in　microtumors　or　micrometastases,　significantly　broadening　the　ICBT　applications　and　offering　a　new　method　for　personalized　and　precise　ICBT.　©　2025　Elsevier　B.V.