The ester–amide exchange reaction between polyamide 6 (PA6) and ethylene-vinyl acetate rubber (EVM) with dibutyltin oxide (DBTO) as a catalyst took place during melt blending, leading to the formation of PA6-grafted EVM copolymer (EVM-g-PA6) and acetamide-terminated PA6. The exchange reaction extent, expressed by the percentage content of the acetate groups taking part in the exchange reaction, was 5.9 mol %, and the yield of EVM-g-PA6 copolymer was 6.8 wt % for PA6/EVM/DBTO (60/40/1) blend at 230°C for 60 min. The number-average molecular weight of PA6 branches in EVM-g-PA6 was ∼278 g/mol as evaluated from nuclear magnetic resonance spectra. The reaction kinetic parameters were calculated according to a second-order reversible reaction mechanism. The rate constant was dependent on the catalyst concentration, PA6/EVM ratio, and shearing conditions. In this article, the characterized ester–amide exchange reaction between PA6 and EVM will guide the fabrication of novel EVM-based graft copolymers and high-performance PA6/EVM thermoplastic elastomers for engineering applications. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40272.