A facile approach based on integrated utilization of ring-opening polymerization (ROP), reversible addition–fragmentation chain transfer (RAFT) process, and azide–alkyne cycloaddition reaction was efficiently used to construct amphiphilic 5-arm ABCDE star quintopolymers. The miktoarm stars are composed of poly(ethylene glycol) (A), poly(e-caprolactone) (B), polystyrene (C), poly(l-lactide) (D), poly(N,N-dimethylaminoethyl methacrylate) (E1), poly(methyl methacrylate) (E2), and poly(methyl acrylate) (E3). Alkyne-in-chain-functionalized BC and DE diblock copolymers were synthesized by successive ROP and RAFT process. Selective [3 + 2] click reaction between two-azide-end-functionalized PEG and BC copolymer gave azide-core-functionalized ABC star terpolymer, and a subsequent click reaction with DE copolymer afforded well-defined ABCDE stars with well-controlled molecular weight, low polydispersity, and precise composition, as evidenced from 1H NMR, GPC, and GPC-MALLS analyses. DSC analyses revealed part of p...