A type of trimaleimide linkers and uses thereof are disclosed. The trimaleimide linkers can be applied for preparation of antibody-drug conjugate as shown by formula I: L-(T-A-D)n I wherein, L is an antibody, antibody fragment or protein; T is a trimaleimide linker; A is a cleavable linker group or a noncleavable linker; D is a drug; n is an integer ranging from 1 to 8.