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Summary: In this study, the effects of exhaust gas recirculation (EGR) on the combustion, performance, and emission of a six‐cylinder turbocharged common‐rail dimethyl ether (DME) engine with methanol blends are experimentally investigated, and the proportions of methanol considered are 0% (DME), 5% (M5), 10% (M10), and 15% (M15) by weight. A comparison of direct‐injection compression ignition (DICI) combustion and partially premixed charge compression ignition (P‐PCCI) combustion is conducted, and P‐PCCI combustion is achieved by a two‐stage injection. The results indicate that the NOx emissions decrease, but the CO and HC emissions increase approximately linearly as the EGR rate increases. The addition of methanol delays the combustion, shortens the combustion duration, and increases the pressure rise rate. In addition, the NOx emissions decrease, whereas the CO and HC emissions increase significantly as the methanol proportion increases. M5 exhibits the lowest fuel consumption for both the P‐PCCI and DICI combustions. Compared to the DICI mode, in the P‐PCCI mode, the peak in‐cylinder pressure is higher, maximum pressure rise rate is considerably lower, NOx emissions are better suppressed and approximately 20% lower, CO and HC emissions are greater, and particle emission is slightly lower. [ABSTRACT FROM AUTHOR]