The invention relates to a non-invasive fetal electrocardiogram detection device and a method for processing electrocardiographic signal data, including a front-end device for collecting electrocardiogram and a software system for analyzing and processing electrocardiographic signals. It specifically includes ECG collecting electrodes, analog-to-digital conversion module, wireless communication module, and core processor module. The signal obtained by the front end of the ECG acquisition is transmitted to the core processing module through the wireless communication module, and the steps of ECG signal quality evaluation, preprocessing, maternal ECG signal analysis and fetal ECG signal analysis and processing are completed, and the maternal and fetal ECG signal is obtained. Heart rate information, combined with waveform morphology analysis, is used to assess the health status of the mother and the status of the fetus in utero. The device can realize long-term, dynamic and real-time analysis and processing of fetal signals of pregnant women, and is of great significance for monitoring the health status of pregnant women and fetuses during pregnancy and childbirth.