Abstract:The Fengtai-Yejituo fault is one of the major faults in the Tangshan area. Its west side is Yahongqiao sag, while its east side is Tangshan rise. There is an obvious difference in the thickness of the Quaternary strata between both sides of the fault. Based on the boreholes on both sides of the fault, this paper makes a preliminary study on its activity since the Quaternary period. Combined with drilling information, the composition of rocks, and the results of the optically stimulated luminescence(OSL) and 14C dating, the Quaternary stratigraphic framework was established according to the magnetic stratigraphy of the boreholes PZK14 and PZK20 which are hanging on the upper and lower plates of the Fengtai-Yejituo fault. The results show that the "boulder-clay layer" at the bottom of the two holes was Neogene sediments. The borehole PZK14 revealed that the buried bottom boundary depth of the Lower Pleistocene, the Middle Pleistocene, the Upper Pleistocene and the Holocene was 387 m, 114 m, 71 m and 6 m, respectively. The borehole PZK20 showed that the buried bottom depth of the Lower Pleistocene, the Middle Pleistocene and the Upper Pleistocene sediments was 155 m, 73 m and 36m respectively, without the Holocene sediments. The activity of Fengtai-Yejituo fault gradually enhanced in the early Pleistocene and its activity rate increased from the early 5.4 cm/ka to 13.9 cm/ka. In the Middle Pleistocene, its activity is basically in a state of stagnation, with an activity rate of 1.0 cm/ka. After the Late Pleistocene, it was reactivated and became more intense active, with activity rate of 54.5 cm/ka.