The invention discloses a portable electrocardiogram monitoring apparatus, which comprises an electrocardiogram acquisition module for acquiring electrocardiogram signals, a DSP (digital signal processor) for receiving and processing the electrocardiogram signals, a memory module for memorizing electrocardiogram data, a storage battery, a display screen for displaying the electrocardiogram signals and a key module, wherein the storage battery is connected to the display screen and the storage battery is connected to the DSP and the electrocardiogram acquisition module by virtue of an LDO (low dropout regulator) voltage-stabilizing circuit; both the key module and the display screen are connected to the DSP; and a communication interface is formed in the DSP. By virtue of the portable electrocardiogram monitoring apparatus disclosed by the invention, electrocardiogram can be monitored at any time, and monitoring data can be observed by virtue of the display screen or transmitted to a monitoring upper computer and observed thereon by virtue of the communication interface, so that abnormal situations can be discovered timely and effective measures can be adopted; therefore, people's body health can be better protected; the portable electrocardiogram monitoring apparatus integrates functions of electrocardiogram signal acquisition, analysis and displaying; and the portable electrocardiogram monitoring apparatus has the advantages of small volume, low cost and strong practicability.