syn-Selective catalytic asymmetric nitro-Mannich reactions using a heterobimetallic Cu/Sm/Schiff base complex are described. The present method is complementary to the previously reported methods, and products were obtained in high syn-selectivity (> 20:1), yield (99-62%), and enantioselectivity (98-83% ee). Both Cu and Sm metals, aligned suitably in a dinucleating Schiff base ligand, were essential to realize high synselectivity.