Zirconium complexes (L₂Zr, L = –OC₆H₂-4-R¹-6-R²-2-CH₂-N[(CH₂)₃-N(CH₂CH₂)₂O]-CH₂-4-R¹-6-R²-C₆H₂O–, R¹ = Me, R² = ^tBu, complex 1; R¹ = R² = ^tBu, complex 2) containing two symmetrical amino-bis(phenolate) ligands were prepared. Moreover, titanium complexes (LTi(OⁱPr)₂, L = –OC₆H₂-4-R¹-6-R²-2-CH₂-N[(CH₂)₃-N(CH₂CH₂)₂O]-CH₂-4-R¹-6-R²-C₆H₂O–, R¹ = Me, R² = ^tBu, complex 3; R¹ = R² = ^tBu, complex 4) based on symmetrical amino-bis(phenolate) ligands were synthesized. These complexes were characterized by ¹H and ¹³C NMR spectroscopy and elemental analyses. The solid-state structures of complexes 2 and 3 were determined by X-ray diffraction. Complexes 1, 2, 3, and 4 were highly active initiators for the ring-opening polymerization of L-lactide (L-LA) and rac-lactide (rac-LA). The experimental results show that complexes 1 and 2 are highly active and excellent catalysts for the immortal ring-opening polymerization (iROP) of L-lactide and rac-lactide in the melt state. The monomer-to-complex ratio reached 200 000/1, which is the highest feeding molar ratio of lactide so far, to the best of our knowledge. Meanwhile, a narrow polydispersity index (1.11–1.58) of polymers was obtained, and the number-average molecular weight approached 8.64 × 10⁴ g mol⁻¹. The turnover frequency (TOF) reached 6593 h⁻¹, and the polymerization proceeded smoothly even in an air environment.