Accurate　diagnosis　and　effective　treatment　of　primary　liver　tumors　are　of　great　significance,　and　optical　imaging　has　been　widely　employed　in　clinical　imaging-guided　surgery　for　liver　tumors.　The　second　near-infrared　window　(NIR-II)　emissive　AIEgen　photosensitizers　have　attracted　a　lot　of　attention　with　higher-resolution　bioimaging　and　deeper　penetration.　NIR-II　aggregation-induced　emission-based　luminogen　(AIEgen)　photosensitizers　have　better　phototherapeutic　effects　and　accuracy　of　the　image-guided　surgery/phototherapy.　Herein,　an　NIR-II　AIEgen　phototheranostic　dot　was　proposed　for　NIR-II　imaging-guided　resection　surgery　and　phototherapy　for　orthotopic　hepatic　tumors.　Compared　with　indocyanine　green　(ICG),　the　AIEgen　dots　showed　bright　and　sharp　NIR-II　emission　at　1250 nm,　which　extended　to　1600 nm　with　high　photostability.　Moreover,　the　AIEgen　dots　efficiently　generated　reactive　oxygen　species　(ROS)　for　photodynamic　therapy.　Investigations　of　orthotopic　liver　tumors　in　vitro　and　in　vivo　demonstrated　that　AIEgen　dots　could　be　employed　both　for　imaging-guided　tumor　surgery　of　early-stage　tumors　and　for　‘downstaging’　intention　to　reduce　the　size.　Moreover,　the　therapeutic　strategy　induced　complete　inhibition　of　orthotopic　tumors　without　recurrence　and　with　few　side　effects.　Graphical　Abstract:　[Figure　not　available:　see　fulltext.].　©　2021,　The　Author(s).