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The Longhai-Zhangpu coastal region lies in the so-called Golden Triangle area of southern Fujian Province. Tectonically, it is located on the southern segment of the Changle-Zhaoan fault zone, being one of the regions of Tertiary and Quaternary basaltic eruptions in Chinas southeast coastal area. In this area there are the Liuhui (Longhai County)-Jiangjunao (Zhangpu County) and Gangwei ( Longhai County)-Huxi ( Zhangpu County) faults, along which basaltic eruption has occurred. The faults have been significantly active since the Quaternary, and several small to moderate earthquakes have occurred on the faults. In this paper, the basic characteristics of the late Quaternary activities and the combination relation of the faults are discussed on the basis of an analysis of along-fault basaltic eruptions during the late Tertiary to late Pleistocene, as well as the differential variation of geomorphic surfaces and marine deposits on both sides of the faults. The results show that the Liuhui-Jiangjunao fault is a late Pleistocene active fault. During the late Tertiary to late Pleistocene, three stages of basaltic eruptions occurred along the fault, among which the first stage occurred in the Pleistocene to early Pleistocene, the second stage in the middle Pleistocene and the third stage in the late Pleistocene. The Gangewei-Huxi fault can also be considered a late Pleistocene active fault. The elevation rate of the downthrown side of the fault is estimated to be 1.11 mm/a.These two faults have dissected the area into the Gangwei graben, south Taiwushan horst and the graben in the sea area to the east of Liuhui-Jiangjunao.