The development of innovative synthetic strategies to create functional polycaprolactones is highly demanded for advanced material applications. In this contribution, we reported a facile synthetic strategy to prepare a class of CL‐based monomers (R‐TO) derived from epoxides. They readily polymerize via well‐controlled ring‐opening polymerization (ROP) to afford a series of polyesters P(R‐TO) with high molecular weight (Mn up to 350 kDa). Sequential addition copolymerization of MTO and L‐lactide (L‐LA) allowed to access of a series of ABA triblock copolymers with composition‐dependent mechanical properties. Notably, P(L‐LA)100‐b‐P(MTO)500‐b‐P(L‐LA)100 containing the amorphous P(MTO) segment as a soft midblock and crystalline P(L‐LA) domain as hard end block behaved as an excellent thermoplastic elastomer (TPE) with high elongation at break (1438 ± 204%), tensile strength (23.5 ± 1.7 MPa), and outstanding elastic recovery (>88%).