The present invention relates to a targeted protease degradation (TED) platform, and specifically to a conjugate of target molecule-linker-E3 ligase ligand as shown in formula I, R
T
-L1-R
E3
(formula I), wherein R
T
is a monovalent group of the target molecule, R
E3
is a monovalent group of the E3 ligase ligand, L1 is the linker linking A and B, and L1 is as shown in formula II below: —W-L2-W
2
— (II).