The invention provides a seaquake monitoring system, and belongs to the field of data acquisition. The seaquake monitoring system comprises an underwater data acquisition end and a water surface data control end, wherein the underwater data acquisition end is connected with the water surface data control end through an optical fiber. The underwater data acquisition end comprises a detector, a preamplifier, an analog filter, a main amplifier, an analog-digital converter and a signal converter; the water surface data control end comprises a human-machine interface, a controller module, a server, a data analysis module, a result generation module, a data transmission module, a data receiving module, and a plurality of signal conversion modules. The seaquake monitoring system meets the high-speed and high-precision acquisition requirement, realizes precise and real-time acquisition of a seismic signal, and can acquire the seismic signal in real time in a high fidelity manner, realize extremely high data resolution and well eliminate various types of interference.