Abstract: In order to further understand the geotectonic characteristics of the Binhai fault zone of the Taiwan Strait, geological, tectonic and geophysical data in the western Taiwan strait are collected and carefully studied. The results suggest that: (1) The geological features, in particular the linear pattern of the three key islands, the Niushan Island, the Brotherhood Island and the Nanpeng Islands, directly reflect the occurrence, nature, sectional distribution pattern and regional variation of the Binhai fault zone; (2) There are three major fault zones in the western Taiwan strait, of which F1, the Binhai fault zone, is a sag-controlling fault and the western boundary of a second-order sag on the Zhejiang-Fujian uplift, F2 a sag-controlling fault, and the eastern boundary of the sag mentioned above, and the F3 fault zone, a basin-controlling fault, the western boundary of the Taixi Basin. The three main fault zones and the normal faults inside the zones together constitute the Western Strait fault system, which controls the formation of the uplifts and sags in the western Taiwan Strait. (3) The Binhai fault zone and Western Strait fault system are cut into five segments by four NW-trending regional faults, i.e. the Pingtan offshore segment, the Quanzhou offshore segment, the Xiamen offshore segment, the Dongshan offshore segment and the Nanao offshore segment from north to south,.