We have devised a highly efficient methodology for the synthesis of high-purity Mn4C, involving arc-melting, subsequent homogenization, and water-quenching steps. This approach overcomes previous constraints associated with limited batch sizes and low purity, enabling the fabrication of substantially larger quantities. In pursuit of achieving the high-purity Mn4C phase, we conducted optimization studies on the stoichiometry of Mn/C in the raw materials, as well as on the homogenization temperature and time. Through this optimization process, we successfully produced highly pure Mn4C ingots by subjecting Mn4.7C alloys to homogenization at temperatures ranging from 1050 to 1200 ℃ for 5 hours, followed by rapid water quenching. The utilization of water quenching served to stabilize the Mn4C phase formed at high temperatures during the homogenization process, thus preventing its transformation into undesired low-temperature phases. The magnetic and physical properties of the samples with highly pure Mn4C phase, quenched from various temperatures, were investigated, revealing subtly distinct characteristics. The pure Mn4C sample obtained by quenching from 1100 °C exhibited a Néel temperature of approximately 950 K, a saturation magnetization of 8.4 Am2/kg, and a positive temperature coefficient (α) of magnetization of 0.0113 Am2/kg·K, respectively. Notably, the abnormal augmentation of thermomagnetic properties over a wide temperature range, from 5 to approximately 650 K, underscores the potential of high-purity Mn4C as a promising candidate for devices where the thermal stability of magnetic properties is of paramount importance.